feat: add page-fetcher-api — centralised Playwright page fetcher

Introduces page-fetcher-api, a new internal ASP.NET Core service that
centralises all web-page fetching through a single Playwright (headless
Chromium) browser instance. All fetches are persisted to the pageFetcher
SQL schema for auditing.

New projects:
- Apis/page-fetcher-api-models: FetchPageRequest, FetchPageResponse, IPageFetcherApiClient
- Apis/page-fetcher-data: PageFetchDbContext, PageFetchEntity, InitialSchema migration (schema: pageFetcher)
- Apis/page-fetcher-api: PlaywrightBrowserService (singleton), PageFetcherService, PageController

Changes to existing services:
- cv-matcher-api: JobTextExtractor now calls IPageFetcherApiClient instead of HttpClient
- cv-search-job: HtmlJobSearcher uses IPageFetcherApiClient (removes inline Playwright);
  CvSearchJobTask fetches individual job pages and applies keyword pre-filter before
  LLM call; passes pre-fetched JobDescription to cv-matcher-api to skip re-fetch
- common: add PageFetcherApiSettings
- docker-compose.yml, build.yml: add new service + env vars for callers

Closes #43

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

Jobs/cv-search-job/cv-search-job.csproj

@@ -13,7 +13,6 @@
     <PackageReference Include="Microsoft.Extensions.Hosting" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" />
     <PackageReference Include="Refit.HttpClientFactory" />
-    <PackageReference Include="Microsoft.Playwright" />
   </ItemGroup>
 
   <ItemGroup>
@@ -26,6 +25,7 @@
     <ProjectReference Include="..\..\Apis\cv-search-data\cv-search-data.csproj" />
     <ProjectReference Include="..\..\Apis\common\common.csproj" />
     <ProjectReference Include="..\..\Apis\email-data\email-data.csproj" />
+    <ProjectReference Include="..\..\Apis\page-fetcher-api-models\page-fetcher-api-models.csproj" />
     <ProjectReference Include="..\..\Helpers\startup-helpers\startup-helpers.csproj" />
     <ProjectReference Include="..\job-scheduler\job-scheduler.csproj" />
   </ItemGroup>