fix(api): use request.app.state in inbox endpoints; preserve dict HTTPException detail

- inbox_lanes, inbox_dismiss_candidates, inbox_export_csv: switch
  module-level 'app' to per-request 'request.app' so per-endpoint
  state stays consistent with the test's TestClient target across
  importlib.reload() (test_api.py::test_cors_extra_origins_via_env
  reloads the api module to mutate CORS allow-lists; pre-reload
  endpoints then mutate the wrong app instance).

- _http_exc_handler: when HTTPException.detail is a dict, wrap under
  'detail' so the standard envelope stays stable and callers can
  branch on body['detail']['error'].

- conftest._auto_init_db: re-resolve cyclone.api.app each fixture
  invocation (instead of caching at module load) so the reload pattern
  doesn't leave event_bus set on a stale app.

- test_acks.test_migration_latest_idempotent_on_fresh_db: bump
  user_version assertion from 12 to 14 after auth migration renumber
  (0013 users+sessions, 0014 audit_log.user_id).

Also installs sqlcipher3 + paramiko into the backend venv so the
capability tests can run; both modules were optional deps that
test_db_crypto and test_sftp_paramiko assume are present.

Backend test results: 1008 passed, 9 skipped (gitignored prodfile
fixtures), 0 failed.

backend/src/cyclone/api.py

@@ -291,6 +291,16 @@ app.include_router(admin.router, dependencies=[Depends(matrix_gate)])
 
 @app.exception_handler(HTTPException)
 async def _http_exc_handler(request, exc: HTTPException):
+    if isinstance(exc.detail, dict):
+        # Endpoints that raise HTTPException with a dict detail (e.g.
+        # ``{"error": "Not found", "detail": "..."}``) want the dict
+        # preserved verbatim so the caller can branch on the `error`
+        # code. Wrap under `detail` for the standard envelope.
+        return JSONResponse(
+            status_code=exc.status_code,
+            content={"detail": exc.detail},
+            headers=exc.headers,
+        )
     code = exc.detail if isinstance(exc.detail, str) else "error"
     return JSONResponse(
         status_code=exc.status_code,
@@ -1107,9 +1117,18 @@ def _serialize_ta1_from_row(row: db.Ta1Ack) -> str:
 
 
 @app.get("/api/inbox/lanes", dependencies=[Depends(matrix_gate)])
-def inbox_lanes():
-    """Return all Inbox lanes in one call."""
-    dismissed_pairs = getattr(app.state, "dismissed_pairs", set())
+def inbox_lanes(request: Request):
+    """Return all Inbox lanes in one call.
+
+    Uses ``request.app.state`` rather than the module-level ``app``
+    global so the endpoint is robust against ``importlib.reload`` of
+    this module (some tests do this to mutate the CORS allow-list).
+    After a reload, the module-level ``app`` rebinds to a new
+    FastAPI instance; ``request.app`` always points at the instance
+    that is actually serving the current request, so per-request
+    state stays consistent with the test's TestClient target.
+    """
+    dismissed_pairs = getattr(request.app.state, "dismissed_pairs", set())
     with db.SessionLocal()() as session:
         from cyclone.inbox_lanes import compute_lanes
         lanes = compute_lanes(session, dismissed_pairs=dismissed_pairs)
@@ -1154,16 +1173,25 @@ def inbox_match_candidate(remit_id: str, body: dict):
 
 
 @app.post("/api/inbox/candidates/dismiss", dependencies=[Depends(matrix_gate)])
-def inbox_dismiss_candidates(body: dict):
-    """Add candidate pairs to the session-scoped dismissed set."""
+def inbox_dismiss_candidates(body: dict, request: Request):
+    """Add candidate pairs to the session-scoped dismissed set.
+
+    Uses ``request.app.state`` rather than the module-level ``app``
+    global so the endpoint is robust against ``importlib.reload`` of
+    this module (some tests do this to mutate the CORS allow-list).
+    After a reload, the module-level ``app`` rebinds to a new
+    FastAPI instance; ``request.app`` always points at the instance
+    that is actually serving the current request, so the test's
+    TestClient target is the one whose state we mutate.
+    """
     pairs = body.get("pairs") or []
-    if not hasattr(app.state, "dismissed_pairs"):
-        app.state.dismissed_pairs = set()
+    if not hasattr(request.app.state, "dismissed_pairs"):
+        request.app.state.dismissed_pairs = set()
     for p in pairs:
         cid = p.get("claim_id")
         rid = p.get("remit_id")
         if cid and rid:
-            app.state.dismissed_pairs.add(frozenset({cid, rid}))
+            request.app.state.dismissed_pairs.add(frozenset({cid, rid}))
     return {"ok": True, "dismissed_count": len(pairs)}
 
 
@@ -1543,11 +1571,16 @@ def export_batch_837(request: Request, batch_id: str, body: dict):
 
 
 @app.get("/api/inbox/export.csv", dependencies=[Depends(matrix_gate)])
-def inbox_export_csv(lane: str):
-    """Stream a CSV for a single lane."""
+def inbox_export_csv(lane: str, request: Request):
+    """Stream a CSV for a single lane.
+
+    Uses ``request.app.state`` rather than the module-level ``app``
+    global so the endpoint is robust against ``importlib.reload`` of
+    this module (see ``inbox_dismiss_candidates`` for context).
+    """
     if lane not in {"rejected", "candidates", "unmatched", "done_today"}:
         raise HTTPException(400, f"unknown lane: {lane}")
-    dismissed_pairs = getattr(app.state, "dismissed_pairs", set())
+    dismissed_pairs = getattr(request.app.state, "dismissed_pairs", set())
     with db.SessionLocal()() as session:
         from cyclone.inbox_lanes import compute_lanes
         lanes = compute_lanes(session, dismissed_pairs=dismissed_pairs)