Add custom architecture function lifting

[tinysec]

Summary

• wire function-level lifting and function architecture-context cleanup callbacks
• add a typed native-owned FunctionLifterContext
• expose platform, logger, blocks, remapping/branch/return inputs, inline result writes, and lifting helpers
• preserve core-owned LLIL builder lifetime with an independent native reference

Verification

• dotnet build --configuration Release (0 warnings, 0 errors)
• targeted real-analysis-pipeline E2E: 1/1
• full external E2E: 289/289