chore: Remove OpenCorporates integration (requires paid plan for commercial use)

Keep only the genuinely free APIs:
- FCA Register (free with registration)
- SRA Register (free public API)
- GitHub (free tier sufficient)
- ORCID (free public API)

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

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

src/RealCV.Application/Models/InternationalCompanyResult.cs

@@ -1,30 +0,0 @@
-namespace RealCV.Application.Models;
-
-/// <summary>
-/// Result of verifying an international company via OpenCorporates
-/// </summary>
-public sealed record InternationalCompanyResult
-{
-    public required string ClaimedCompany { get; init; }
-    public required string ClaimedJurisdiction { get; init; }
-    public required bool IsVerified { get; init; }
-
-    // Matched company details
-    public string? MatchedCompanyName { get; init; }
-    public string? CompanyNumber { get; init; }
-    public string? Jurisdiction { get; init; }
-    public string? JurisdictionCode { get; init; }
-    public string? CompanyType { get; init; }
-    public string? Status { get; init; }
-    public DateOnly? IncorporationDate { get; init; }
-    public DateOnly? DissolutionDate { get; init; }
-    public string? RegisteredAddress { get; init; }
-
-    // OpenCorporates specific
-    public string? OpenCorporatesUrl { get; init; }
-    public DateTime? DataLastUpdated { get; init; }
-
-    public int MatchScore { get; init; }
-    public string? VerificationNotes { get; init; }
-    public List<CompanyVerificationFlag> Flags { get; init; } = [];
-}