Fix six audit findings: dead code, missing status records, missing fallback, unsafe JSON read

create_task.py:
- Remove dead make_client() call before the verify branch; it was called
  unconditionally with host=None/key=None, creating a broken client that was
  immediately discarded or overwritten.
- Remove "verify" from the dispatch dict; it was never reached through dispatch
  (the if/cmd==verify branch above it handled it). Dispatch now only contains
  commands that actually use a client.
- Wrap json.load() in try/except (OSError, JSONDecodeError) so a corrupt or
  partially-written status file produces a useful message instead of a traceback.

sitecustomize.py:
- Call _record_status() on the early-return paths in both _patch_b2 and
  _patch_restic. Without this, if TrueNAS natively supports B2 or the patch
  is already applied, the status file was never written and `verify` always
  reported failure even when everything was fine.
- Add idempotency guard to _record_status(): first call wins; duplicate calls
  for the same module are ignored so the entry count stays accurate.
- Make B2 get_restic_config a @staticmethod. The method never used self; the
  noqa comment was suppressing the evidence of a design mismatch. Removing the
  unused parameter makes the intent explicit.
- Add NamedTuple._replace() fallback after dataclasses.replace() in the restic
  wrapper. If ResticConfig is ever refactored to a NamedTuple, the TypeError
  from dataclasses.replace() would have surfaced as a backup job failure rather
  than a graceful recovery.

patch/create_task.py

@@ -92,8 +92,14 @@ def cmd_verify(_client, _args):
         print(f"  Expected: {_STATUS_FILE}")
         sys.exit(1)
 
-    with open(_STATUS_FILE, encoding="utf-8") as fh:
-        status = json.load(fh)
+    try:
+        with open(_STATUS_FILE, encoding="utf-8") as fh:
+            status = json.load(fh)
+    except (OSError, json.JSONDecodeError) as exc:
+        print(f"Could not read status file: {exc}")
+        print(f"  Path: {_STATUS_FILE}")
+        print("Try restarting middlewared to regenerate it.")
+        sys.exit(1)
 
     print(f"Hook status (recorded at {status.get('patched_at', 'unknown')})")
     print()
@@ -225,22 +231,21 @@ def main():
                    help="Create the task in a disabled state")
 
     args = p.parse_args()
-    client = make_client(args.host, args.api_key, args.insecure)
 
+    if args.cmd == "verify":
+        cmd_verify(None, args)
+        return
+
+    if not args.host or not args.api_key:
+        p.error("--host and --api-key are required for this command")
+
+    client = make_client(args.host, args.api_key, args.insecure)
     dispatch = {
-        "verify":           cmd_verify,
         "list-credentials": cmd_list_credentials,
         "list-tasks":       cmd_list_tasks,
         "create":           cmd_create,
     }
-
-    if args.cmd == "verify":
-        cmd_verify(None, args)
-    else:
-        if not args.host or not args.api_key:
-            p.error("--host and --api-key are required for this command")
-        client = make_client(args.host, args.api_key, args.insecure)
-        dispatch[args.cmd](client, args)
+    dispatch[args.cmd](client, args)
 
 
 if __name__ == "__main__":