Add LLM Council mode for multi-model consensus

3-stage council orchestration: parallel model queries (Stage 1),
anonymous peer ranking (Stage 2), and streamed chairman synthesis
(Stage 3). Includes scope-aware file resolution for Google/Claude
providers so upstream file attachments are visible to all providers.

- Backend: council.py orchestrator, /api/run_council_stream endpoint,
  query_model_full() non-streaming wrapper, resolve_provider() helper,
  resolve_scoped_file_ids() for Google/Claude scope parity with OpenAI
- Frontend: council toggle UI, model checkbox selector, chairman picker,
  SSE event parsing, tabbed Stage 1/2/3 response display
- Canvas: amber council node indicator with Users icon

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 17 insertions, 1 deletions

diff --git a/backend/app/schemas.py b/backend/app/schemas.py
index 8e5f12c..a527004 100644
--- a/backend/app/schemas.py
+++ b/backend/app/schemas.py
@@ -34,7 +34,7 @@ class LLMConfig(BaseModel):
     provider: ModelProvider
     model_name: str
     temperature: float = 0.7
-    max_tokens: int = 1000
+    max_tokens: Optional[int] = None
     system_prompt: Optional[str] = None
     api_key: Optional[str] = None  # Optional override, usually from env
     enable_google_search: bool = False
@@ -55,6 +55,22 @@ class NodeRunRequest(BaseModel):
     # Contains all project/node combinations in the current trace
     scopes: List[str] = Field(default_factory=list)
     
+class CouncilMemberConfig(BaseModel):
+    model_name: str  # e.g. "gpt-5", "claude-opus-4-6", "gemini-3-pro-preview"
+
+class CouncilRunRequest(BaseModel):
+    node_id: str
+    incoming_contexts: List[Context] = []
+    user_prompt: str
+    council_models: List[CouncilMemberConfig]  # 2-6 models
+    chairman_model: str  # Model name for synthesis
+    system_prompt: Optional[str] = None
+    temperature: float = 0.7
+    reasoning_effort: ReasoningEffort = ReasoningEffort.MEDIUM
+    merge_strategy: MergeStrategy = MergeStrategy.SMART
+    attached_file_ids: List[str] = Field(default_factory=list)
+    scopes: List[str] = Field(default_factory=list)
+
 class NodeRunResponse(BaseModel):
     node_id: str
     output_context: Context