feat(providers): add headless browser scraping via Playwright for SPA job sites

ejobs.ro migrated to a Nuxt SPA - plain HTTP GET returns only the JS
bundle. This change equips cv-search-job with a headless Chromium
(Playwright 1.60) so it can fully render SPA pages before extracting
job links.

- Add UseHeadlessBrowser flag to JobProviderEntity, JobProviderConfig,
  and CvSearchDbContext; map it in JobTokenService.ToConfig so the flag
  is included in the session provider-config snapshot
- Migration: add UseHeadlessBrowser column; fix ejobs.ro search URL
  (remove /user/ prefix that caused 404) and set UseHeadlessBrowser=true
- HtmlJobSearcher: detect flag and dispatch to FetchWithPlaywrightAsync;
  plain-HTTP path is unchanged; NetworkIdle timeout falls back to partial
  content rather than failing outright
- Dockerfile: download Playwright Chromium in the SDK build stage via
  npx; copy browser binaries to the final image; install Chromium system
  libs (Ubuntu noble t64 variants)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Apis/cv-search-data/Data/CvSearchDbContext.cs

@@ -79,6 +79,7 @@ public sealed class CvSearchDbContext : DbContext
             entity.Property(x => x.InitialKeywordsJson).HasMaxLength(2000).HasDefaultValue("[]").IsRequired();
             entity.Property(x => x.MaxResults).HasDefaultValue(20);
             entity.Property(x => x.DisplayOrder).HasDefaultValue(0);
+            entity.Property(x => x.UseHeadlessBrowser).HasDefaultValue(false);
         });
     }
 }

Apis/cv-search-data/Data/Entities/JobProviderEntity.cs

@@ -30,4 +30,7 @@ public sealed class JobProviderEntity
 
     /// <summary>Controls display ordering in future admin UIs.</summary>
     public int DisplayOrder { get; set; }
+
+    /// <summary>When true, the scraper renders the page with headless Chromium instead of a plain HTTP GET.</summary>
+    public bool UseHeadlessBrowser { get; set; }
 }

Apis/cv-search-data/Migrations/20260529170000_AddHeadlessBrowserToProviders.Designer.cs

@@ -0,0 +1,234 @@
+// <auto-generated />
+using System;
+using CvSearch.Data;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+#nullable disable
+
+namespace CvSearch.Data.Migrations
+{
+    [DbContext(typeof(CvSearchDbContext))]
+    [Migration("20260529170000_AddHeadlessBrowserToProviders")]
+    partial class AddHeadlessBrowserToProviders
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasDefaultSchema("cvSearch")
+                .HasAnnotation("ProductVersion", "10.0.7")
+                .HasAnnotation("Relational:MaxIdentifierLength", 128);
+
+            SqlServerModelBuilderExtensions.UseIdentityColumns(modelBuilder);
+
+            modelBuilder.Entity("CvSearch.Data.Entities.JobProviderEntity", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("Id"));
+
+                    b.Property<int>("DisplayOrder")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int")
+                        .HasDefaultValue(0);
+
+                    b.Property<bool>("Enabled")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("InitialKeywordsJson")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(2000)
+                        .HasColumnType("nvarchar(2000)")
+                        .HasDefaultValue("[]");
+
+                    b.Property<string>("JobLinkContains")
+                        .IsRequired()
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<int>("MaxResults")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int")
+                        .HasDefaultValue(20);
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("SearchUrlTemplate")
+                        .IsRequired()
+                        .HasMaxLength(1024)
+                        .HasColumnType("nvarchar(1024)");
+
+                    b.Property<bool>("UseHeadlessBrowser")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bit")
+                        .HasDefaultValue(false);
+
+                    b.HasKey("Id");
+
+                    b.ToTable("JobProviders", "cvSearch");
+                });
+
+            modelBuilder.Entity("CvSearch.Data.Entities.JobSearchResultEntity", b =>
+                {
+                    b.Property<string>("Id")
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("datetime2")
+                        .HasDefaultValueSql("SYSUTCDATETIME()");
+
+                    b.Property<string>("JobText")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("JobTitle")
+                        .IsRequired()
+                        .HasMaxLength(512)
+                        .HasColumnType("nvarchar(512)");
+
+                    b.Property<string>("JobUrl")
+                        .IsRequired()
+                        .HasMaxLength(2048)
+                        .HasColumnType("nvarchar(2048)");
+
+                    b.Property<string>("ProviderName")
+                        .IsRequired()
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.Property<string>("ResultJson")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<int>("Score")
+                        .HasColumnType("int");
+
+                    b.Property<string>("SessionId")
+                        .IsRequired()
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("SessionId");
+
+                    b.ToTable("JobSearchResults", "cvSearch");
+                });
+
+            modelBuilder.Entity("CvSearch.Data.Entities.JobSearchSessionEntity", b =>
+                {
+                    b.Property<string>("Id")
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("datetime2")
+                        .HasDefaultValueSql("SYSUTCDATETIME()");
+
+                    b.Property<string>("CvDocumentId")
+                        .IsRequired()
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.Property<string>("Email")
+                        .IsRequired()
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<string>("Keywords")
+                        .IsRequired()
+                        .HasMaxLength(1000)
+                        .HasColumnType("nvarchar(1000)");
+
+                    b.Property<string>("Language")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(8)
+                        .HasColumnType("nvarchar(8)")
+                        .HasDefaultValue("en");
+
+                    b.Property<string>("ProviderConfigJson")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Status")
+                        .IsRequired()
+                        .HasMaxLength(32)
+                        .HasColumnType("nvarchar(32)");
+
+                    b.Property<string>("TokenId")
+                        .IsRequired()
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("Status");
+
+                    b.ToTable("JobSearchSessions", "cvSearch");
+                });
+
+            modelBuilder.Entity("CvSearch.Data.Entities.JobSearchTokenEntity", b =>
+                {
+                    b.Property<string>("Id")
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("datetime2")
+                        .HasDefaultValueSql("SYSUTCDATETIME()");
+
+                    b.Property<string>("CvDocumentId")
+                        .IsRequired()
+                        .HasMaxLength(64)
+                        .HasColumnType("nvarchar(64)");
+
+                    b.Property<string>("Email")
+                        .IsRequired()
+                        .HasMaxLength(256)
+                        .HasColumnType("nvarchar(256)");
+
+                    b.Property<DateTime>("ExpiresAt")
+                        .HasColumnType("datetime2");
+
+                    b.Property<string>("Keywords")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(1000)
+                        .HasColumnType("nvarchar(1000)")
+                        .HasDefaultValue("");
+
+                    b.Property<string>("Language")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(8)
+                        .HasColumnType("nvarchar(8)")
+                        .HasDefaultValue("en");
+
+                    b.Property<bool>("Used")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bit")
+                        .HasDefaultValue(false);
+
+                    b.HasKey("Id");
+
+                    b.ToTable("JobSearchTokens", "cvSearch");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Apis/cv-search-data/Migrations/20260529170000_AddHeadlessBrowserToProviders.cs

@@ -0,0 +1,50 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace CvSearch.Data.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddHeadlessBrowserToProviders : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<bool>(
+                name: "UseHeadlessBrowser",
+                schema: MigrationConstants.SchemaName,
+                table: "JobProviders",
+                type: "bit",
+                nullable: false,
+                defaultValue: false);
+
+            // ejobs.ro (Id=1) is a Nuxt SPA — the old /user/ URL 404s and plain HTTP GET
+            // returns only the JS bundle, not actual job listings.
+            // Fix: use the correct search URL and headless Chromium to render job results.
+            migrationBuilder.UpdateData(
+                schema: MigrationConstants.SchemaName,
+                table: "JobProviders",
+                keyColumn: "Id",
+                keyValue: 1,
+                columns: ["SearchUrlTemplate", "JobLinkContains", "UseHeadlessBrowser"],
+                values: new object[] { "https://www.ejobs.ro/locuri-de-munca?q={keywords}", "/locuri-de-munca/", true });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.UpdateData(
+                schema: MigrationConstants.SchemaName,
+                table: "JobProviders",
+                keyColumn: "Id",
+                keyValue: 1,
+                columns: ["SearchUrlTemplate", "JobLinkContains", "UseHeadlessBrowser"],
+                values: new object[] { "https://www.ejobs.ro/user/locuri-de-munca/?utm_source=myai&q={keywords}", "/user/locuri-de-munca/", false });
+
+            migrationBuilder.DropColumn(
+                name: "UseHeadlessBrowser",
+                schema: MigrationConstants.SchemaName,
+                table: "JobProviders");
+        }
+    }
+}

Apis/cv-search-data/Migrations/CvSearchDbContextModelSnapshot.cs

@@ -66,6 +66,11 @@ namespace CvSearch.Data.Migrations
                         .HasMaxLength(1024)
                         .HasColumnType("nvarchar(1024)");
 
+                    b.Property<bool>("UseHeadlessBrowser")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bit")
+                        .HasDefaultValue(false);
+
                     b.HasKey("Id");
 
                     b.ToTable("JobProviders", "cvSearch");