Each DbContext now explicitly configures its migration history table to use
the schema-qualified name pattern [schemaName].[_Migrations]:
- [cvMatcher].[_Migrations] for CvMatcherDbContext
- [emailApi].[_Migrations] for EmailApiDbContext
- [cvSearch].[_Migrations] for CvSearchDbContext
- [rag].[_Migrations] for RagDbContext
- [myAi].[_Migrations] for MyAiDbContext
This is done via OnConfiguring() with UseSqlServer().MigrationsHistoryTable(name, schema).
Removed incorrect rename migrations that were created due to misunderstanding
of the proper EF Core configuration approach.
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>