feat: DB-backed localized templates + language-aware emails

- New Apis/myai-models project: MyAiDbContext (schema myAi), TemplateEntity,
  ITemplateService, DbTemplateService with 10-min in-memory cache
- Seeds EN+RO variants for all user-facing templates (match email, job search
  results email, HTML status pages, AI system prompt)
- Match result email now sent in user's UI language (en/ro)
- Job search results email now respects session language
- Language propagates: MatchJobRequest -> token -> session -> email
- Add Language column to JobSearchTokens and JobSearchSessions (default 'en')
- All three Dockerfiles updated to include myai-models in build context

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

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

@@ -98,6 +98,13 @@ namespace CvSearch.Models.Migrations
                         .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)");
 
@@ -142,6 +149,13 @@ namespace CvSearch.Models.Migrations
                     b.Property<DateTime>("ExpiresAt")
                         .HasColumnType("datetime2");
 
+                    b.Property<string>("Language")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(8)
+                        .HasColumnType("nvarchar(8)")
+                        .HasDefaultValue("en");
+
                     b.Property<bool>("Used")
                         .ValueGeneratedOnAdd()
                         .HasColumnType("bit")