Treat Venice as a tool-capable SOTA cloud provider (#1173)

Follow-up to the Venice provider PR. Wire api.venice.ai into the three
host allowlists so Venice behaves like the other paid OpenAI-compatible
clouds:

- agent_loop: add api.venice.ai to _API_HOSTS so the agent sends native
  OpenAI tool-call schemas (Venice supports function calling) instead of
  degrading to fenced-block parsing.
- teacher_escalation: add api.venice.ai to _SOTA_HOSTS so the escalation
  loop stays OFF for Venice (it's a paid top-tier API; no need to add
  teacher-model latency).
- webhook_routes: add venice to KNOWN_PROVIDERS so the sync chat webhook
  can auto-resolve base_url from provider=venice.

Tests: tests/test_venice_hosts.py pins tool-host matching + SOTA
classification for Venice; py_compile on touched modules.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/agent_loop.py

@@ -457,7 +457,7 @@ _API_HOSTS = frozenset([
     "api.deepseek.com", "deepseek.com",
     "api.together.xyz", "api.fireworks.ai",
     "api.perplexity.ai", "api.x.ai",
-    "ollama.com",
+    "ollama.com", "api.venice.ai",
     # Local OpenAI-compatible endpoints (llama.cpp, vLLM, LM Studio, etc.).
     # Without these, `_is_api_model` falls back to keyword sniffing on the
     # model name, so well-behaved local servers don't get native tool