The memory Engine tab quick-select built its model list only from a
keyword heuristic over the chat catalog plus OpenRouter live discovery,
so configured providers whose embedding models are not in that catalog
(e.g. Cloudflare Workers AI cf/@cf/baai/bge-m3) never appeared, and
requests for them failed with 'Unknown embedding provider'.
- add cloudflare-ai to EMBEDDING_PROVIDERS with a requiresAccountId URL
template resolved per-request via buildEmbeddingProviderUrl() (mirrors
CloudflareAIExecutor on the chat side) plus the cf provider alias
- merge curated registry models into the quick-select catalog and add a
generic fallback listing: any configured OpenAI-compatible chat
provider without a curated entry appears with free-text model input
- same treatment for rerank: listRerankProviders + generic Cohere-
compatible fallback, new /api/memory/rerank-providers endpoint,
selectors fall back to free-text when no static models exist
- runtime: embeddings service/handler and rerank route/handler resolve
derived providers instead of rejecting unlisted ones
