When SOCRATICODE_PROJECT_ID is set to share a Qdrant collection across
git worktrees, the indexer still used absolute paths as keys in the file
hash map, chunk IDs, and for deleting file chunks. This caused every
worktree to see all files as "new" and trigger a full re-index, defeating
the purpose of the shared project ID feature.
Switch all internal keying from absolute paths to relative paths:
- chunkId() now hashes on relativePath for stable IDs across worktrees
- File hash map (change detection) keyed by relativePath
- deleteFileChunks() filters on relativePath Qdrant field
- Deleted file detection uses relative path sets
Absolute paths are now only used for actual file I/O (stat, readFile).
When working with git worktrees (or any setup where the same codebase lives
in multiple directories), each path currently gets its own Qdrant collection.
This means the same codebase is indexed multiple times.
This change adds a SOCRATICODE_PROJECT_ID environment variable that, when set,
overrides the path-based project ID generation. All directories sharing the
same SOCRATICODE_PROJECT_ID will use the same Qdrant collections (codebase,
codegraph, context), eliminating redundant indexing.
The value must match [a-zA-Z0-9_-]+ to remain Qdrant-friendly. An error is
thrown at startup if the value contains invalid characters.
Csaba Tuncsik