feat(deps): python-telegram-bot 21.5 -> 22.8

Salto mayor revisado contra el changelog oficial:
- La 22.0 elimina lo deprecado en v20.x. De esa lista el bot solo usaba
  disable_web_page_preview (3 sitios), que ademas resulta seguir vivo
  como shim en 22.8 — se migra igualmente a link_preview_options, que
  es la API canonica desde Bot API 7.0.
- No usamos quote=, proxy_url, ni *_timeout en run_polling (el resto
  de eliminaciones). Python >=3.10 (imagen 3.12) y httpx >=0.27,<0.29
  (tenemos 0.28.1) OK.
- Verificado aislado: import de src.bot.bot sin DeprecationWarnings,
  8 tests en verde.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

requirements.txt

@@ -1,5 +1,5 @@
 # Core
-python-telegram-bot==21.5
+python-telegram-bot==22.8
 httpx==0.28.1
 aiohttp==3.14.1
 

src/bot/bot.py

@@ -10,7 +10,7 @@ from typing import Optional
 from zoneinfo import ZoneInfo
 
 import structlog
-from telegram import Update, Message
+from telegram import Update, Message, LinkPreviewOptions
 from telegram.ext import (
     Application, CommandHandler, MessageHandler,
     filters, ContextTypes
@@ -397,7 +397,7 @@ async def cmd_generate(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
                 await update.message.reply_text(
                     generator.last_publish_notice,
                     parse_mode=ParseMode.MARKDOWN,
-                    disable_web_page_preview=True,
+                    link_preview_options=LinkPreviewOptions(is_disabled=True),
                 )
             except Exception as e:
                 logger.warning("Failed to send SEO summary message", error=str(e))
@@ -526,7 +526,10 @@ async def cmd_news(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
 
         items = [item_from_row(r) for r in recent]
         for chunk in format_digest(items):
-            await update.message.reply_text(chunk, disable_web_page_preview=False)
+            # Previews activos a propósito (el digest gana con la tarjeta del link).
+            await update.message.reply_text(
+                chunk, link_preview_options=LinkPreviewOptions(is_disabled=False)
+            )
     finally:
         await db_conn.close()
 
@@ -969,7 +972,7 @@ async def _scheduler_loop(app: Application):
                                 for c in chunks:
                                     await app.bot.send_message(
                                         chat_id=news_chat_id, text=c,
-                                        disable_web_page_preview=False,
+                                        link_preview_options=LinkPreviewOptions(is_disabled=False),
                                     )
                                 # Marca todos los pendientes (incluidos los "…y N más")
                                 await db.mark_news_notified([r["id"] for r in pending])