feat: add EN/ES/RO language selector for AI pitch generation

- db.py: add `language` column to ai_queue; migration; queue_ai() accepts
  language param and re-queues with ON CONFLICT UPDATE so changing language works
- main.py: batch and single assess endpoints accept `language` from request body
- enricher.py: ai_worker_loop reads language column, passes to _assess_one()
- replicate_ai.py: assess_domain() and _build_prompt() accept language param;
  OUTPUT LANGUAGE section injected into prompt so Gemini writes pitch/email in
  the requested language (EN/ES/RO)
- index.html: flag dropdown (🇪🇸/🇬🇧/🇷🇴) next to AI Assess button; aiLang
  state default ES; language sent in all batch assessment requests

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

app/db.py

@@ -52,7 +52,8 @@ CREATE TABLE IF NOT EXISTS ai_queue (
     status TEXT DEFAULT 'pending',
     created_at TEXT DEFAULT (datetime('now')),
     completed_at TEXT,
-    error TEXT
+    error TEXT,
+    language TEXT DEFAULT 'ES'
 );
 CREATE TABLE IF NOT EXISTS scores (
     domain TEXT PRIMARY KEY,
@@ -74,6 +75,7 @@ _MIGRATIONS = [
     "ALTER TABLE enriched_domains ADD COLUMN ai_assessed_at TEXT",
     "ALTER TABLE enriched_domains ADD COLUMN site_analysis TEXT",
     "CREATE TABLE IF NOT EXISTS ai_queue (domain TEXT PRIMARY KEY, status TEXT DEFAULT 'pending', created_at TEXT DEFAULT (datetime('now')), completed_at TEXT, error TEXT)",
+    "ALTER TABLE ai_queue ADD COLUMN language TEXT DEFAULT 'ES'",
 ]
 
 # Index build state
@@ -332,11 +334,12 @@ async def get_enriched(min_score=0, cms=None, country=None, kit_digital=None, pa
     return total, rows
 
 
-async def queue_ai(domains: list[str]):
+async def queue_ai(domains: list[str], language: str = "ES"):
     async with aiosqlite.connect(SQLITE_PATH) as db:
         await db.executemany(
-            "INSERT OR IGNORE INTO ai_queue (domain) VALUES (?)",
-            [(d,) for d in domains],
+            """INSERT INTO ai_queue (domain, language) VALUES (?, ?)
+               ON CONFLICT(domain) DO UPDATE SET language=excluded.language, status='pending'""",
+            [(d, language) for d in domains],
         )
         await db.commit()