app: P2 migrations (year/seller_type/extras) + importer backfill, guards idempotent

- db.init_db gains guarded ALTER TABLE additions for listings.year /
  seller_type / extras (schema.sql v1 untouched; PRAGMA-checked idempotent)
- rubric: extras_from_text() returns matched EXTRAS labels (table order)
- importer: normalize computes year (existing helper), seller_type ONLY
  from a real state-item signal (dealer/private, else NULL), extras JSON;
  upsert rewrites the new columns on both paths
- verified on live DB: import idempotent, counts stay 640/560/80, year
  backfilled on 599 rows, extras on 45, seller_type 0 (no state signal)

app/db.py

@@ -23,7 +23,19 @@ def connect(db_path):
 
 
 def init_db(conn):
-    """Apply schema.sql (idempotent)."""
+    """Apply schema.sql (idempotent) + guarded P2 column migrations.
+
+    P2 additions (docs/DATA-MODEL.md) are added with idempotent
+    ``ALTER TABLE ... ADD COLUMN`` guarded by a PRAGMA check, so the locked
+    v1 schema.sql stays untouched and existing DBs migrate in place.
+    """
     with open(SCHEMA_PATH, encoding='utf-8') as fh:
         conn.executescript(fh.read())
+    cols = {r['name'] for r in conn.execute("PRAGMA table_info('listings')")}
+    if 'year' not in cols:
+        conn.execute('ALTER TABLE listings ADD COLUMN year INTEGER')
+    if 'seller_type' not in cols:
+        conn.execute('ALTER TABLE listings ADD COLUMN seller_type TEXT')
+    if 'extras' not in cols:
+        conn.execute('ALTER TABLE listings ADD COLUMN extras TEXT')
     conn.commit()

app/importer.py

@@ -101,6 +101,12 @@ def normalize(region, src_id, it, now):
         km = None  # 0 km is a placeholder, not delivery mileage
     year = rubric.year_from_title(title)
     score, family = rubric.score_item(title, it.get('desc') or '', price_num, km, year)
+    extras = rubric.extras_from_text(title, it.get('desc') or '')
+    # seller_type only from a REAL signal in the state item (the hunt image
+    # backfill / enrichment passes) — never inferred from titles.
+    seller = it.get('seller_type') or it.get('seller')
+    if seller not in ('dealer', 'private'):
+        seller = None
     return {
         'region': region,
         'src_id': src_id,
@@ -114,6 +120,9 @@ def normalize(region, src_id, it, now):
         'desc': it.get('desc') or None,
         'family': family,
         'score': score,
+        'year': year,
+        'seller_type': seller,
+        'extras': json.dumps(extras) if extras else None,
         'first_seen': it.get('first_seen') or now,
         'last_seen': now,
     }
@@ -130,20 +139,24 @@ def upsert(conn, row, now):
         conn.execute(
             '''UPDATE listings SET title=?, price_display=?, price_num=?, km=?,
                location=?, url=?, img_url=?, desc=?, family=?, score=?,
+               year=?, seller_type=?, extras=?,
                status='active', dup_of=NULL, last_seen=?, updated_at=?
                WHERE id=?''',
             (row['title'], row['price_display'], row['price_num'], row['km'],
              row['location'], row['url'], row['img_url'], row['desc'],
-             row['family'], row['score'], now, now, existing['id']))
+             row['family'], row['score'], row['year'], row['seller_type'],
+             row['extras'], now, now, existing['id']))
         return existing['id'], False
     cur = conn.execute(
         '''INSERT INTO listings (region, src_id, title, price_display, price_num,
-           km, location, url, img_url, desc, family, score, status, dup_of,
+           km, location, url, img_url, desc, family, score, year, seller_type,
+           extras, status, dup_of,
            first_seen, last_seen, created_at, updated_at)
-           VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)''',
+           VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)''',
         (row['region'], row['src_id'], row['title'], row['price_display'],
          row['price_num'], row['km'], row['location'], row['url'],
-         row['img_url'], row['desc'], row['family'], row['score'], 'active',
+         row['img_url'], row['desc'], row['family'], row['score'], row['year'],
+         row['seller_type'], row['extras'], 'active',
          None, row['first_seen'], row['last_seen'], now, now))
     return cur.lastrowid, True
 

app/rubric.py

@@ -146,6 +146,16 @@ def score_item(title, desc, price_num, km, year=None):
     return s, label
 
 
+def extras_from_text(title, desc):
+    """Return the labels of every EXTRAS pattern that matches title+desc.
+
+    One entry per label (labels are unique in the EXTRAS table); order is
+    the table order. Stored on listings.extras at import (P2).
+    """
+    text = (title + ' ' + desc).lower()
+    return [label for pat, _pts, label in EXTRAS if re.search(pat, text)]
+
+
 def year_from_title(title):
     """Extract a model year from the title, or None."""
     m = re.search(r'\b(19\d\d|20[0-2]\d)\b', title or '')