Add XML doc to all service interfaces and implementations (#26)

- Update CLAUDE.md: replace incorrect 'no XML doc on internal code' rule
  with the correct convention (XML doc on all public methods and
  non-trivial private/protected helpers)
- Restore /// <summary> on FileDownloadController private helpers
  (HandleRangeRequest, StreamRangeAsync)
- Add full XML doc to all service contracts:
  ICaptchaVerifier, IEmailSender, ICvMatcherService, IJobTextExtractor,
  IJobTokenService, IDocumentClassifier, IRagService, ITextChunker,
  ITextExtractor, IEmailTemplateService, ITemplateService
- Add /// <summary> and /// <inheritdoc /> to all concrete service classes
  and their methods: RecaptchaVerifier, EmailApiEmailSender,
  SmtpEmailDispatcher, CvMatcherService, JobTextExtractor, JobTokenService,
  RagService, DocumentClassifier, TextChunker, TextExtractor,
  HtmlJobSearcher, CvSearchEmailSender, CvSearchJobTask,
  EmailTemplateService, DbTemplateService

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

Apis/cv-matcher-api/Services/Contracts/ICvMatcherService.cs

@@ -3,9 +3,34 @@ using CvMatcher.Models.Responses;
 
 namespace Api.Services.Contracts;
 
+/// <summary>
+/// Orchestrates CV indexing, job matching, and job discovery operations.
+/// </summary>
 public interface ICvMatcherService
 {
+    /// <summary>
+    /// Indexes a CV PDF into the RAG system and returns document metadata.
+    /// Returns cached metadata without re-indexing when the same text hash already exists.
+    /// </summary>
+    /// <param name="file">Uploaded CV PDF file.</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>Upload response with document ID, hash, and indexing statistics.</returns>
     Task<CvUploadResponse> UploadCvAsync(IFormFile file, CancellationToken ct);
+
+    /// <summary>
+    /// Scores a CV against a specific job posting URL or pasted description using the LLM.
+    /// Caches the result so repeat requests for the same (CV, job, language) triple are served instantly.
+    /// </summary>
+    /// <param name="request">Match request containing CV document ID, job URL or description, and language preference.</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>Structured match response with score, summary, strengths, gaps, and recommendations.</returns>
     Task<JobMatchResponse> MatchJobAsync(MatchJobRequest request, CancellationToken ct);
+
+    /// <summary>
+    /// Searches the RAG index for job documents most similar to the given CV and scores the top candidates.
+    /// </summary>
+    /// <param name="request">Request containing the CV document ID and optional result count limit.</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>Response with the CV document ID and a list of ranked match results.</returns>
     Task<FindJobsResponse> FindJobsAsync(FindJobsRequest request, CancellationToken ct);
 }

Apis/cv-matcher-api/Services/Contracts/IJobTextExtractor.cs

@@ -1,6 +1,17 @@
 namespace Api.Services.Contracts;
 
+/// <summary>
+/// Extracts plain text from a job posting, either from a pasted description or by fetching and parsing a URL.
+/// </summary>
 public interface IJobTextExtractor
 {
+    /// <summary>
+    /// Returns normalised plain text for the job posting.
+    /// Prefers <paramref name="jobDescription"/> when provided; otherwise fetches and strips HTML from <paramref name="jobUrl"/>.
+    /// </summary>
+    /// <param name="jobUrl">URL of the job posting page, used when no description is pasted.</param>
+    /// <param name="jobDescription">Pasted job description text; takes priority over URL fetching.</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>Normalised plain text, truncated to the configured maximum character limit.</returns>
     Task<string> ExtractAsync(string? jobUrl, string? jobDescription, CancellationToken ct);
 }

Apis/cv-matcher-api/Services/Contracts/IJobTokenService.cs

@@ -1,7 +1,29 @@
 namespace Api.Services.Contracts;
 
+/// <summary>
+/// Manages one-time job search tokens and the sessions they trigger.
+/// </summary>
 public interface IJobTokenService
 {
+    /// <summary>
+    /// Creates a new single-use job search token linked to the given CV document and user.
+    /// The token expires after the number of days configured in <c>JobSearch:TokenExpiryDays</c>.
+    /// </summary>
+    /// <param name="cvDocumentId">Identifier of the indexed CV document.</param>
+    /// <param name="email">Email address of the user who will receive the results.</param>
+    /// <param name="language">Preferred language for result emails (e.g. <c>"en"</c>, <c>"ro"</c>).</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>The generated token ID, to be embedded in the one-click job search link.</returns>
     Task<string> CreateTokenAsync(string cvDocumentId, string email, string language, CancellationToken ct);
+
+    /// <summary>
+    /// Validates the token and, if valid, marks it as used and creates a <c>Pending</c> job search session.
+    /// </summary>
+    /// <param name="tokenId">The token ID from the one-click link.</param>
+    /// <param name="ct">Cancellation token.</param>
+    /// <returns>
+    /// One of the <c>StartJobSearchStatus</c> string constants:
+    /// <c>Started</c>, <c>AlreadyUsed</c>, <c>Expired</c>, or <c>NotFound</c>.
+    /// </returns>
     Task<string> TriggerStartAsync(string tokenId, CancellationToken ct);
 }

Apis/cv-matcher-api/Services/CvMatcherService.cs

@@ -10,6 +10,9 @@ using Microsoft.Extensions.Options;
 
 namespace Api.Services;
 
+/// <summary>
+/// Orchestrates CV upload, RAG indexing, job text extraction, LLM scoring, and result caching.
+/// </summary>
 public sealed class CvMatcherService : ICvMatcherService
 {
     private readonly IRagApiClient _rag;
@@ -35,6 +38,7 @@ public sealed class CvMatcherService : ICvMatcherService
         _settings = options.Value;
     }
 
+    /// <inheritdoc />
     public async Task<CvUploadResponse> UploadCvAsync(IFormFile file, CancellationToken ct)
     {
         var response = await _rag.IndexCvPdfAsync(file, ct);
@@ -51,6 +55,7 @@ public sealed class CvMatcherService : ICvMatcherService
         };
     }
 
+    /// <inheritdoc />
     public async Task<FindJobsResponse> FindJobsAsync(FindJobsRequest request, CancellationToken ct)
     {
         var cv = await _rag.GetDocumentAsync(request.CvDocumentId, ct) ?? throw new InvalidOperationException("CV document not found.");
@@ -78,6 +83,7 @@ public sealed class CvMatcherService : ICvMatcherService
         return new FindJobsResponse { CvDocumentId = request.CvDocumentId, Jobs = jobs };
     }
 
+    /// <inheritdoc />
     public async Task<JobMatchResponse> MatchJobAsync(MatchJobRequest request, CancellationToken ct)
     {
         if (!request.GdprConsent) throw new InvalidOperationException("GDPR consent is required.");
@@ -104,6 +110,11 @@ public sealed class CvMatcherService : ICvMatcherService
         return await ScorePairAsync(cv, jobDocument, matchedChunks, request.Email, NormalizeLanguage(request.Language), ct);
     }
 
+    /// <summary>
+    /// Scores a (CV, job) pair with the LLM.
+    /// Returns a cached result immediately when the same (CV, job, language) triple has been scored before.
+    /// When no evidence chunks are available from the vector search, falls back to the raw job text.
+    /// </summary>
     private async Task<JobMatchResponse> ScorePairAsync(RagDocumentDetails cv, RagDocumentDetails job, IReadOnlyList<string> evidenceChunks, string? email, string language, CancellationToken ct)
     {
         var cached = await _repository.GetMatchAsync(cv.Id, job.Id, language, ct);
@@ -138,6 +149,10 @@ public sealed class CvMatcherService : ICvMatcherService
         return result;
     }
 
+    /// <summary>
+    /// Deserialises the LLM's JSON output into a <see cref="JobMatchResponse"/>.
+    /// Returns a safe fallback response instead of throwing when the JSON cannot be parsed.
+    /// </summary>
     private static JobMatchResponse ParseResult(string json)
     {
         try
@@ -158,21 +173,29 @@ public sealed class CvMatcherService : ICvMatcherService
         };
     }
 
+    /// <summary>
+    /// Builds a descriptive search query from the CV text for use in vector similarity search.
+    /// </summary>
     private static string BuildCvSearchProfile(string cvText)
     {
         var text = Limit(cvText, 10000);
         return $"Candidate profile, skills, technologies, seniority, industry experience, project experience: {text}";
     }
 
+    /// <summary>
+    /// Extracts a short job title from the first sentence-like fragment of the job text.
+    /// </summary>
     private static string ExtractJobTitle(string jobText)
     {
         var first = jobText.Split('.', '\n', '\r').Select(x => x.Trim()).FirstOrDefault(x => x.Length is > 8 and < 140);
         return first ?? "Job description";
     }
 
+    /// <summary>Returns the base language code, lower-cased, defaulting to <c>"en"</c>.</summary>
     private static string NormalizeLanguage(string? language) =>
         string.IsNullOrWhiteSpace(language) ? "en" : language.ToLowerInvariant().Split('-')[0].Trim();
 
+    /// <summary>Maps a language code to its full English name for use in the LLM system prompt.</summary>
     private static string LanguageName(string language) => language switch
     {
         "ro" => "Romanian",
@@ -180,5 +203,6 @@ public sealed class CvMatcherService : ICvMatcherService
         _ => "English"
     };
 
+    /// <summary>Truncates <paramref name="value"/> to at most <paramref name="max"/> characters.</summary>
     private static string Limit(string value, int max) => value.Length <= max ? value : value[..max];
 }

Apis/cv-matcher-api/Services/JobTextExtractor.cs

@@ -6,6 +6,10 @@ using Microsoft.Extensions.Options;
 
 namespace Api.Services;
 
+/// <summary>
+/// Extracts normalised plain text from a job posting, either from a pasted description or by
+/// fetching and stripping the HTML of the job page URL.
+/// </summary>
 public sealed class JobTextExtractor : IJobTextExtractor
 {
     private readonly HttpClient _http;
@@ -19,6 +23,7 @@ public sealed class JobTextExtractor : IJobTextExtractor
         _http.DefaultRequestHeaders.UserAgent.ParseAdd("MyAi.ro CV Matcher/1.0");
     }
 
+    /// <inheritdoc />
     public async Task<string> ExtractAsync(string? jobUrl, string? jobDescription, CancellationToken ct)
     {
         var pasted = Normalize(jobDescription ?? string.Empty);
@@ -37,12 +42,14 @@ public sealed class JobTextExtractor : IJobTextExtractor
         return Limit(Normalize(WebUtility.HtmlDecode(html)));
     }
 
+    /// <summary>Truncates text to the configured maximum character count.</summary>
     private string Limit(string value)
     {
         var max = Math.Max(4000, _settings.MaxJobTextChars);
         return value.Length <= max ? value : value[..max];
     }
 
+    /// <summary>Collapses all whitespace runs to single spaces and trims the result.</summary>
     private static string Normalize(string value)
     {
         if (string.IsNullOrWhiteSpace(value)) return string.Empty;

Apis/cv-matcher-api/Services/JobTokenService.cs

@@ -11,6 +11,9 @@ using Microsoft.Extensions.Options;
 
 namespace Api.Services;
 
+/// <summary>
+/// Creates and validates one-time job search tokens, and creates the corresponding search sessions.
+/// </summary>
 public sealed class JobTokenService : IJobTokenService
 {
     private readonly CvSearchDbContext _db;
@@ -30,6 +33,7 @@ public sealed class JobTokenService : IJobTokenService
         _logger = logger;
     }
 
+    /// <inheritdoc />
     public async Task<string> CreateTokenAsync(string cvDocumentId, string email, string language, CancellationToken ct)
     {
         var token = new JobSearchTokenEntity
@@ -49,6 +53,7 @@ public sealed class JobTokenService : IJobTokenService
         return token.Id;
     }
 
+    /// <inheritdoc />
     public async Task<string> TriggerStartAsync(string tokenId, CancellationToken ct)
     {
         var token = await _db.JobSearchTokens.FirstOrDefaultAsync(x => x.Id == tokenId, ct);
@@ -86,6 +91,10 @@ public sealed class JobTokenService : IJobTokenService
         return StartJobSearchStatus.Started;
     }
 
+    /// <summary>
+    /// Extracts up to 10 meaningful keywords from the CV text using simple heuristics (no LLM).
+    /// Takes the first 5 usable lines, splits them into words, strips punctuation, and deduplicates.
+    /// </summary>
     private static string ExtractKeywords(string cvText)
     {
         var lines = cvText