feat: Add additional verification APIs (FCA, SRA, GitHub, OpenCorporates, ORCID)

This adds five new free API integrations for enhanced CV verification:

- FCA Register API: Verify financial services professionals
- SRA Register API: Verify solicitors and legal professionals
- GitHub API: Verify developer profiles and technical skills
- OpenCorporates API: Verify international companies across jurisdictions
- ORCID API: Verify academic researchers and publications

Includes:
- API clients for all five services with retry policies
- Service implementations with name matching and validation
- Models for verification results with detailed flags
- Configuration options in appsettings.json
- DI registration for all services

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/RealCV.Application/Models/GitHubVerificationResult.cs

@@ -0,0 +1,52 @@
+namespace RealCV.Application.Models;
+
+/// <summary>
+/// Result of verifying a developer's GitHub profile
+/// </summary>
+public sealed record GitHubVerificationResult
+{
+    public required string ClaimedUsername { get; init; }
+    public required bool IsVerified { get; init; }
+
+    // Profile details
+    public string? ProfileName { get; init; }
+    public string? ProfileUrl { get; init; }
+    public string? Bio { get; init; }
+    public string? Company { get; init; }
+    public string? Location { get; init; }
+    public DateOnly? AccountCreated { get; init; }
+
+    // Activity metrics
+    public int PublicRepos { get; init; }
+    public int Followers { get; init; }
+    public int Following { get; init; }
+    public int TotalContributions { get; init; }
+
+    // Language breakdown
+    public Dictionary<string, int> LanguageStats { get; init; } = new();
+
+    // Claimed skills verification
+    public List<SkillVerification> SkillVerifications { get; init; } = [];
+
+    public string? VerificationNotes { get; init; }
+    public List<GitHubVerificationFlag> Flags { get; init; } = [];
+}
+
+public sealed record SkillVerification
+{
+    public required string ClaimedSkill { get; init; }
+    public required bool IsVerified { get; init; }
+    public int RepoCount { get; init; }
+    public int TotalLinesOfCode { get; init; }
+    public DateOnly? FirstUsed { get; init; }
+    public DateOnly? LastUsed { get; init; }
+    public string? Notes { get; init; }
+}
+
+public sealed record GitHubVerificationFlag
+{
+    public required string Type { get; init; }
+    public required string Severity { get; init; }
+    public required string Message { get; init; }
+    public int ScoreImpact { get; init; }
+}