Fix: accept task_code/milestone_code as identifiers, add /config/status endpoint

- All /tasks/{task_id} endpoints now accept both numeric id and task_code string
- All /milestones/{milestone_id} endpoints (misc.py) now accept both numeric id and milestone_code
- Added _resolve_task() and _resolve_milestone() helpers
- GET /config/status reads initialization state from config volume (no wizard dependency)
- MilestoneResponse schema now includes milestone_code field
- Comments and worklog endpoints also accept task_code

app/schemas/schemas.py

@@ -240,6 +240,7 @@ class MilestoneUpdate(BaseModel):
 
 class MilestoneResponse(MilestoneBase):
     id: int
+    milestone_code: Optional[str] = None
     project_id: int
     created_by_id: Optional[int] = None
     started_at: Optional[datetime] = None