fix: resolve all critical runtime errors and bugs from audit

- Add COMPLETIONS_API_KEY to config.py (env var + auto-generated fallback)
- Fix perplexity auto-search: upstream sends logprobs=true, parse_llama_stream_chunk
  extracts per-token logprobs, all_logprobs populated during streaming
- Fix all /api/models endpoints to target LLAMA_SERVER_BASE (port 8081) not OLLAMA_BASE
- Fix RAG embedding endpoint URL from port 11434 (Ollama) to 8081 (llama-server)
- Correct misleading error messages: 'inference server' not 'Ollama'
- Remove raw_results leak from SSE event stream in /api/search
- Fix weather query extractor: pattern-match instead of unconditional suffix append
- Escape FTS5 operator keywords (AND/OR/NOT/NEAR) in memory search
- Move auth.py BODY_LIMIT_DEFAULT_BYTES imports to module level
- Change RAG injection log level from warning to info
- Fix all 8 test files after modular refactor (rewire imports from correct modules)
- Update AGENTS.md and README.md to reflect v1.8.0 changes

memory.py

@@ -62,7 +62,13 @@ def search_memories(query: str, limit: int = 5) -> list:
     if not words:
         db.close()
         return []
-    safe_query = " OR ".join(word + "*" for word in words[:10])
+    escaped = []
+    for word in words[:10]:
+        if word.upper() in {"AND", "OR", "NOT", "NEAR"}:
+            escaped.append(f'"{word}"*')
+        else:
+            escaped.append(word + "*")
+    safe_query = " OR ".join(escaped)
     try:
         rows = db.execute(
             "SELECT rowid, fact, topic, source, created_at, bm25(memories) AS rank "