Extract Di lifetime parsing primitives for Captive Dependency (#232)

[Skymly]

Summary

• Introduce DesignPatterns.Analyzers.Di with shared Lifetime and LifetimeResolution primitives (expression + invocation-argument resolution).
• Wire CaptiveDependencyAnalyzer to those primitives and remove duplicated private ResolveLifetime logic.
• Add InternalsVisibleTo plus unit tests for lifetime-resolution edge cases; keep existing Captive Dependency Verify behaviour frozen.

Test plan

• dotnet test tests/DesignPatterns.Analyzers.Tests --filter FullyQualifiedName~DiLifetimeResolutionTests
• dotnet test tests/DesignPatterns.Analyzers.Tests --filter FullyQualifiedName~CaptiveDependency|FullyQualifiedName~FactoryDelegateCaptive
• dotnet test DesignPatterns.slnx -c Release
• CI green on this PR

Closes #232

Made with Cursor

[Skymly]

Review (#232)

Spec

• DesignPatterns.Analyzers.Di exposes Lifetime + LifetimeResolution (TryResolve / TryResolveArgument)
• CaptiveDependencyAnalyzer uses the shared primitives; private ResolveLifetime* removed on covered paths
• InternalsVisibleTo(DesignPatterns.Analyzers.Tests)
• Unit tests cover constant / unknown / named / positional / omitted-argument cases (not only Verify)
• Captive Dependency Verify behaviour frozen; CI green (build-test, build-test-net48, samples, pack)

Out of scope as designed: registration map (#233+), LifetimeMismatchAnalyzer still keeps its private copy (#236).

Standards / notes

• Extraction matches agreed seams; internal + IVT is the right visibility for analyzer primitives.
• No behaviour change beyond the move — good for a freeze ticket.
• Minor nit (non-blocking): DiLifetimeResolutionTests repeats the Holder.Register fixture three times — fine to tidy later when #236 lands and more call sites share the helper.

Verdict

LGTM — ready to merge.