fix: test DB isolation, Discord recovery, and over-mocked tests

Test data was bleeding into production tasks.db because
swarm.task_queue.models.DB_PATH (relative path) was never patched in
conftest.clean_database. Fixed by switching to absolute paths via
settings.repo_root and adding the missing module to the patching list.

Discord bot could leak orphaned clients on retry after ERROR state.
Added _cleanup_stale() to close stale client/task before each start()
attempt, with improved logging in the token watcher.

Rewrote test_paperclip_client.py to use httpx.MockTransport instead of
patching _get/_post/_delete — tests now exercise real HTTP status codes,
error handling, and JSON parsing. Added end-to-end test for
capture_error → create_task DB isolation.

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

src/dashboard/routes/work_orders.py

@@ -9,13 +9,14 @@ from pathlib import Path
 from fastapi import APIRouter, Form, HTTPException, Request
 from fastapi.responses import HTMLResponse
 
+from config import settings
 from dashboard.templating import templates
 
 logger = logging.getLogger(__name__)
 
 router = APIRouter(tags=["work-orders"])
 
-DB_PATH = Path("data/work_orders.db")
+DB_PATH = Path(settings.repo_root) / "data" / "work_orders.db"
 
 PRIORITIES = ["low", "medium", "high", "critical"]
 CATEGORIES = ["bug", "feature", "suggestion", "maintenance", "security"]