Replace AutoMapper with explicit FromModel() extension methods in V3 API

[Copilot]

Context

AutoMapper adds implicit magic that makes mapping logic hard to trace. Replacing it with explicit static FromModel() methods makes the data flow obvious and removes a runtime dependency on reflection-based mapping.

Changes proposed in this pull request

Removed AutoMapper infrastructure:

• Deleted all 12 MapperProfile.cs files across V20240101–V20260416
• Removed AutoMapper NuGet package reference
• Removed global using AutoMapper, AddAutoMapper() service registration, and the ITypeConverter<,> Scrutor scan
• Deleted Infrastructure/Mapping/OptionMapper.cs (generic Option/OneOf type converters no longer needed)

Added explicit mapping:

• Static FromModel() factory methods on all V3 response records (e.g. GetPersonResponse.FromModel(result))
• Extension methods for DTOs shared across versions: TrnRequestInfo, QtsInfo, alert types, induction info, routes-to-professional-status, etc.
• Extension files placed in TeachingRecordSystem.Api where they reference Api-layer types, and in TeachingRecordSystem.Core where they reference only Core types

Updated all V3 controllers to drop IMapper constructor injection and call FromModel() directly:

// Before
return result.ToActionResult(r => Ok(mapper.Map<GetPersonResponse>(r)));

// After
return result.ToActionResult(r => Ok(GetPersonResponse.FromModel(r)));

Guidance to review

• Each API version has its own FromModel() implementation; look for version-specific field additions (e.g. AwardedOrApprovedCount added in V20250327's QtsInfo)
• Where extension method ambiguity arose between versions (e.g. QtsInfo.FromModel() in V20240814 vs V20250327), the mapping is inlined directly in the response record rather than using an extension method
• The V20250627/DtoExtensions.cs in the Api project handles the richer route-to-professional-status mapping that references both Postgres model types and Implementation DTOs

Checklist

• Attach to Trello card
• Rebased master
• Cleaned commit history
• Tested by running locally