feat: add "blocked for human input" feature across full stack

Agents can now request structured human input when they encounter
genuine blockers (API keys, design choices, external configs). The
request is displayed in the UI with a dynamic form, and the human's
response is stored and made available when the agent resumes.

Changes span 21 files + 1 new component:
- Database: 3 new columns (needs_human_input, human_input_request,
  human_input_response) with migration
- MCP: new feature_request_human_input tool + guards on existing tools
- API: new resolve-human-input endpoint, 4th feature bucket
- Orchestrator: skip needs_human_input features in scheduling
- Progress: 4-tuple return from count_passing_tests
- WebSocket: needs_human_input count in progress messages
- UI: conditional 4th Kanban column, HumanInputForm component,
  amber status indicators, dependency graph support

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

server/routers/features.py

@@ -23,6 +23,7 @@ from ..schemas import (
     FeatureListResponse,
     FeatureResponse,
     FeatureUpdate,
+    HumanInputResponse,
 )
 from ..utils.project_helpers import get_project_path as _get_project_path
 from ..utils.validation import validate_project_name
@@ -104,6 +105,9 @@ def feature_to_response(f, passing_ids: set[int] | None = None) -> FeatureRespon
         in_progress=f.in_progress if f.in_progress is not None else False,
         blocked=blocked,
         blocking_dependencies=blocking,
+        needs_human_input=getattr(f, 'needs_human_input', False) or False,
+        human_input_request=getattr(f, 'human_input_request', None),
+        human_input_response=getattr(f, 'human_input_response', None),
     )
 
 
@@ -143,11 +147,14 @@ async def list_features(project_name: str):
             pending = []
             in_progress = []
             done = []
+            needs_human_input_list = []
 
             for f in all_features:
                 feature_response = feature_to_response(f, passing_ids)
                 if f.passes:
                     done.append(feature_response)
+                elif getattr(f, 'needs_human_input', False):
+                    needs_human_input_list.append(feature_response)
                 elif f.in_progress:
                     in_progress.append(feature_response)
                 else:
@@ -157,6 +164,7 @@ async def list_features(project_name: str):
                 pending=pending,
                 in_progress=in_progress,
                 done=done,
+                needs_human_input=needs_human_input_list,
             )
     except HTTPException:
         raise
@@ -341,9 +349,11 @@ async def get_dependency_graph(project_name: str):
                 deps = f.dependencies or []
                 blocking = [d for d in deps if d not in passing_ids]
 
-                status: Literal["pending", "in_progress", "done", "blocked"]
+                status: Literal["pending", "in_progress", "done", "blocked", "needs_human_input"]
                 if f.passes:
                     status = "done"
+                elif getattr(f, 'needs_human_input', False):
+                    status = "needs_human_input"
                 elif blocking:
                     status = "blocked"
                 elif f.in_progress:
@@ -564,6 +574,71 @@ async def skip_feature(project_name: str, feature_id: int):
         raise HTTPException(status_code=500, detail="Failed to skip feature")
 
 
+@router.post("/{feature_id}/resolve-human-input", response_model=FeatureResponse)
+async def resolve_human_input(project_name: str, feature_id: int, response: HumanInputResponse):
+    """Resolve a human input request for a feature.
+
+    Validates all required fields have values, stores the response,
+    and returns the feature to the pending queue for agents to pick up.
+    """
+    project_name = validate_project_name(project_name)
+    project_dir = _get_project_path(project_name)
+
+    if not project_dir:
+        raise HTTPException(status_code=404, detail=f"Project '{project_name}' not found in registry")
+
+    if not project_dir.exists():
+        raise HTTPException(status_code=404, detail="Project directory not found")
+
+    _, Feature = _get_db_classes()
+
+    try:
+        with get_db_session(project_dir) as session:
+            feature = session.query(Feature).filter(Feature.id == feature_id).first()
+
+            if not feature:
+                raise HTTPException(status_code=404, detail=f"Feature {feature_id} not found")
+
+            if not getattr(feature, 'needs_human_input', False):
+                raise HTTPException(status_code=400, detail="Feature is not waiting for human input")
+
+            # Validate required fields
+            request_data = feature.human_input_request
+            if request_data and isinstance(request_data, dict):
+                for field_def in request_data.get("fields", []):
+                    if field_def.get("required", True):
+                        field_id = field_def.get("id")
+                        if field_id not in response.fields or response.fields[field_id] in (None, ""):
+                            raise HTTPException(
+                                status_code=400,
+                                detail=f"Required field '{field_def.get('label', field_id)}' is missing"
+                            )
+
+            # Store response and return to pending queue
+            from datetime import datetime, timezone
+            response_data = {
+                "fields": {k: v for k, v in response.fields.items()},
+                "responded_at": datetime.now(timezone.utc).isoformat(),
+            }
+            feature.human_input_response = response_data
+            feature.needs_human_input = False
+            # Keep in_progress=False, passes=False so it returns to pending
+
+            session.commit()
+            session.refresh(feature)
+
+            # Compute passing IDs for response
+            all_features = session.query(Feature).all()
+            passing_ids = {f.id for f in all_features if f.passes}
+
+            return feature_to_response(feature, passing_ids)
+    except HTTPException:
+        raise
+    except Exception:
+        logger.exception("Failed to resolve human input")
+        raise HTTPException(status_code=500, detail="Failed to resolve human input")
+
+
 # ============================================================================
 # Dependency Management Endpoints
 # ============================================================================

server/routers/projects.py

@@ -102,7 +102,7 @@ def get_project_stats(project_dir: Path) -> ProjectStats:
     """Get statistics for a project."""
     _init_imports()
     assert _count_passing_tests is not None  # guaranteed by _init_imports()
-    passing, in_progress, total = _count_passing_tests(project_dir)
+    passing, in_progress, total, _needs_human_input = _count_passing_tests(project_dir)
     percentage = (passing / total * 100) if total > 0 else 0.0
     return ProjectStats(
         passing=passing,