Fix Phase 0 compilation errors - validation fixes

Resolved 22 compilation errors:
- Fixed lib.rs re-exports to use correct submodule paths
- Added missing submodule declarations to module files
- Created stub files for referenced submodules
- Fixed main.rs imports to use lib.rs re-exports

Project now compiles successfully with only 2 expected warnings:
- dead_code warning for jobs field in JobManager
- unused_variable warning for job_manager in main

Both warnings are expected for scaffolding phase.

.a0proj/memory/index.faiss.sha256

@@ -1 +1 @@
-0599a7a9889d5d3a7c1fb03f0f613cb6901427fa5123e69550f71a073490737b
+5e47d269127461e182add6522c34ac4b8cd45d554c4d8b6802c147d71964d2a0