Address the gemini-code-assist review on #1671:
- Wrap `http.client.HTTPException` (BadStatusLine / IncompleteRead — common
with local/overloaded servers) and `ValueError` (invalid/missing URL scheme;
also subsumes `json.JSONDecodeError`) in `EmbeddingAPIError` instead of
letting them crash the caller.
- Reject a non-dict top-level JSON response before calling `.get()` on it, so a
JSON list/`null`/string yields a clear `EmbeddingAPIError` rather than an
unhandled `AttributeError`.
- Add tests for all three cases.
Add an `embedding_model: "openai-compat"` option that computes embeddings
via any OpenAI-compatible `/v1/embeddings` server (LM Studio, llama.cpp,
vLLM, Ollama's OpenAI shim, self-hosted) instead of a local ONNX model.
- New OpenAICompatEmbeddingFunction (stdlib urllib, no new dependency):
batches requests, asks for `encoding_format: "float"` and a custom
User-Agent (avoids Cloudflare 403, see #1570), validates the response
(contiguous 0..n-1 indices + well-formed vectors) before use, and
L2-normalizes for the cosine collection. Exposes `embed_query` (ChromaDB
1.5 dispatches query embedding through it, not `__call__`). `name()`
encodes the model id so switching it forces `mempalace repair
rebuild-index`. Failures raise a module-specific `EmbeddingAPIError`.
- Endpoint settings resolved by MempalaceConfig as a single source of truth:
`embedding_api_url` / `embedding_api_model` / `embedding_api_key`, each
overridable via the matching `MEMPALACE_EMBEDDING_API_*` env var.
Whitespace-only values are treated as unset; the EF cache key fingerprints
the key so a token rotation is picked up.
- The miner/MCP `Device:` header reports `openai-compat (<url>)` instead of a
misleading local accelerator label when this backend is active.
- Opt-in; default stays minilm. Mirrors the existing `openai-compat` LLM
provider naming; stays local when the endpoint is on the machine/LAN.
- Tests: tests/test_embedding_api.py (no server / no network required).
- Docs: README requirement note, module docstring, CHANGELOG.
Refs #1559.
maximilize