feat: decouple market from shared_lib, add app-owned models

Phase 1-3 of decoupling:
- path_setup.py adds project root to sys.path
- Market-owned models in market/models/ (market, market_place)
- All imports updated: shared.infrastructure, shared.db, shared.browser, etc.
- MarketPlace uses container_type/container_id instead of post_id FK

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

scrape/product/helpers/desc.py

@@ -2,10 +2,10 @@
 from __future__ import annotations
 from typing import Dict, List, Optional, Tuple
 from bs4 import BeautifulSoup, NavigableString, Tag
-from utils import normalize_text
+from shared.utils import normalize_text
 from ...html_utils import absolutize_fragment
 from .text import clean_title, is_blacklisted_heading
-from config import config
+from shared.config import config
 
 
 def split_description_container(desc_el: Tag) -> Tuple[str, List[Dict]]:

scrape/product/helpers/html.py

@@ -2,7 +2,7 @@
 from __future__ import annotations
 from typing import List, Optional
 from urllib.parse import urljoin, urlparse
-from config import config
+from shared.config import config
 
 def first_from_srcset(val: str) -> Optional[str]:
     if not val:

scrape/product/helpers/text.py

@@ -1,8 +1,8 @@
 
 from __future__ import annotations
 import re
-from utils import normalize_text
-from config import config
+from shared.utils import normalize_text
+from shared.config import config
 
 def clean_title(t: str) -> str:
     t = normalize_text(t)