feat(llm): route adapters by provider

examples/sandbox-acp-agent/cordis.yml

@@ -18,8 +18,6 @@
   config:
     apiKey: !!js process.env.DEEPSEEK_API_KEY
     baseURL: !!js process.env.DEEPSEEK_BASE_URL
-    models:
-      - deepseek-v4-flash
 
 # The sandbox stack: the platform-runner provider (bwrap → per-platform
 # Landlock launcher → Seatbelt, functionally probed), then the confined bash executor.
@@ -49,6 +47,7 @@
 - id: acp-agent
   name: '@deepseek-ai/dsh-acp-agent'
   config:
+    provider: deepseek
     model: deepseek-v4-flash
     # Persistence root: $DSH_SNAPSHOT_SESSIONS_ROOT when the snapshot harness
     # sets it (so a record run's logs land where the harness harvests them),