chore(lint): auto-fix 253 of 283 ruff issues (F401, I001, E402, RUF100, UP037, SIM105)

Mass ruff auto-fix:
  - ruff check --fix: 109 issues fixed (F401 unused imports,
    I001 unsorted imports, UP037 quoted annotations, SIM105
    suppressible exception, RUF100 unused-noqa)
  - ruff check --fix --unsafe-fixes: 22 additional issues
  - ruff format: 70 files reformatted
  - Manual pass: fix 16 misplaced import httpx lines
  - Manual pass: fix remaining E402 (import-after-docstring)

Result: 283 errors -> 30 errors.

The remaining 30 are real issues that need manual review:
  5 F401 unused-import (likely auto-generated stubs)
  5 F821 undefined-name (real bugs in code that references
    redis/pydantic/LLMRegistry without imports)
  3 BLE001 (the compliance LLM fallback is intentional; the
    other two are real)
  3 RUF012 mutable-class-default
  3 SIM105, 3 SIM117, 2 E722, 2 E741
  1 B007, 1 B025, 1 E402, 1 RUF200 (pyproject.toml issue)

Tests: 436/437 pass (1 pre-existing SSE sandbox failure).
format check + import sort: now clean.
make ci: still gated on the 30 remaining real issues.
Follow-up: triage the 30 issues file-by-file.

structure_monitor.py

@@ -1,26 +1,23 @@
-import httpx
+
 """Pry — Page Structure Monitor.
 Track CSS selector validity over time. Alert before scrapers break."""
-from paths import PRY_DATA_DIR
-
 # SPDX-License-Identifier: MIT
 # Copyright (c) 2026 Rug Munch Media LLC
 #
 # Part of Pry — https://git.rugmunch.io/RugMunchMedia/pryscraper
 # Licensed under MIT. See LICENSE.
-
 import hashlib
 import json
 import logging
-import os
 from contextlib import suppress
 from datetime import UTC, datetime
-from pathlib import Path
 from typing import Any
 
+import httpx
 from lxml import html as lxml_html
 
 from client import get_client
+from paths import PRY_DATA_DIR
 
 logger = logging.getLogger(__name__)