Refactor memory package layers

[codeaholicguy]

Summary

• Reorganize @ai-devkit/memory internals into database, repositories, services, domain/knowledge, and semantic layers while preserving public facades.
• Move semantic config into the service config layer for future service-level configuration growth.
• Restructure unit and integration tests to mirror the new package layers and remove direct test-local store/update/search workflow clones.
• Add lifecycle docs for the refactor plan, implementation notes, and validation evidence.

Validation

• npm --workspace @ai-devkit/memory test
• npm --workspace @ai-devkit/memory run typecheck
• npm --workspace @ai-devkit/memory run lint
• npm --workspace @ai-devkit/memory run build
• npx ai-devkit@latest lint --feature memory-package-refactor
• pre-commit hook: full repo lint and full repo tests passed (92 files, 1113 tests)

Risk

• Medium review surface due to broad file moves, but external package exports and command facades are preserved and covered by compatibility tests.

[GuilhermeMReis]

nice one