Registration map: explicit container registrations

[Skymly]

What to build

Add a registration map Build that records type→lifetime from explicit container registrations (MSDI Add*/TryAdd, Autofac RegisterType/Register, and the explicit parts of that scan). Captive Dependency constructor analysis (DP062) for those entries reads the map. Attributed RegisterDi expansion and factory-delegate DP066 are out of scope.

Acceptance criteria

• DiRegistrationMap.Build (or equivalent) produces type→lifetime for explicit container registrations
• Captive Dependency DP062 for those registrations is driven from the map
• Unit tests assert map entries for representative MSDI/Autofac/TryAdd shapes
• Existing DP062 Verify coverage for explicit registrations stays green (behaviour freeze)

Blocked by

#232 — Di lifetime parsing primitives + InternalsVisibleTo