* feat: replace WASM embeddings with persistent chroma-mcp MCP connection
Replace ChromaServerManager (npx chroma run + chromadb npm + ONNX/WASM)
with ChromaMcpManager, a singleton stdio MCP client that communicates with
chroma-mcp via uvx. This eliminates native binary issues, segfaults, and
WASM embedding failures that plagued cross-platform installs.
Key changes:
- Add ChromaMcpManager: singleton MCP client with lazy connect, auto-reconnect,
connection lock, and Zscaler SSL cert support
- Rewrite ChromaSync to use MCP tool calls instead of chromadb npm client
- Handle chroma-mcp's non-JSON responses (plain text success/error messages)
- Treat "collection already exists" as idempotent success
- Wire ChromaMcpManager into GracefulShutdown for clean subprocess teardown
- Delete ChromaServerManager (no longer needed)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix: address PR review — connection guard leak, timer leak, async reset
- Clear connecting guard in finally block to prevent permanent reconnection block
- Clear timeout after successful connection to prevent timer leak
- Make reset() async to await stop() before nullifying instance
- Delete obsolete chroma-server-manager test (imports deleted class)
- Update graceful-shutdown test to use chromaMcpManager property name
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix: prevent chroma-mcp spawn storm — zombie cleanup, stale onclose guard, reconnect backoff
Three bugs caused chroma-mcp processes to accumulate (92+ observed):
1. Zombie on timeout: failed connections left subprocess alive because
only the timer was cleared, not the transport. Now catch block
explicitly closes transport+client before rethrowing.
2. Stale onclose race: old transport's onclose handler captured `this`
and overwrote the current connection reference after reconnect,
orphaning the new subprocess. Now guarded with reference check.
3. No backoff: every failure triggered immediate reconnect. With
backfill doing hundreds of MCP calls, this created rapid-fire
spawning. Added 10s backoff on both connection failure and
unexpected process death.
Also includes ChromaSync fixes from PR review:
- queryChroma deduplication now preserves index-aligned arrays
- SQL injection guard on backfill ID exclusion lists
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Alex Newman
40daf8f3fa