feat: trackeo de coste por llamada Claude — tabla api_usage + /costs

src/bot/bot.py

@@ -78,6 +78,7 @@ async def cmd_start(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
         "`/generate <type>` — Generate output (podcast|blog|report|thread)\n"
         "`/sources` — List all sources found\n"
         "`/outputs` — List generated outputs\n"
+        "`/costs` — Show API usage costs\n"
         "`/cancel` — Cancel current research\n"
         "`/help` — Show this message",
         parse_mode=ParseMode.MARKDOWN
@@ -419,6 +420,57 @@ async def cmd_outputs(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
         await db_conn.close()
 
 
+async def cmd_costs(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
+    if not is_authorized(update.effective_user.id):
+        return
+
+    chat_id = update.effective_chat.id
+    db_conn = await get_db()
+    db = ResearchDB(db_conn)
+
+    try:
+        cursor = await db_conn.execute(
+            "SELECT * FROM research_sessions WHERE telegram_chat_id = ? ORDER BY created_at DESC LIMIT 1",
+            (chat_id,)
+        )
+        row = await cursor.fetchone()
+        if not row:
+            await update.message.reply_text("No sessions found.")
+            return
+
+        session_id = row["id"]
+        topic = row["topic"]
+
+        by_type = {r["call_type"]: r for r in await db.get_usage_stats(session_id)}
+        totals = await db.get_total_usage_stats()
+
+        lines = [f"📊 *Costes ResearchOwl*\n"]
+        lines.append(f"Última sesión (`{topic}`):")
+
+        session_total = 0.0
+        for call_type, label in [("scoring", "Scoring"), ("generation", "Generación")]:
+            row_data = by_type.get(call_type)
+            if row_data:
+                calls = row_data["calls"]
+                tokens = row_data["total_tokens"]
+                cost = row_data["total_cost"]
+                session_total += cost
+                lines.append(f"  {label}:    {calls} llamadas · {tokens:,} tokens · ${cost:.4f}")
+            else:
+                lines.append(f"  {label}:    —")
+
+        lines.append(f"  Total:      ${session_total:.4f}")
+        lines.append("")
+        lines.append("Acumulado total:")
+        acc_cost = totals.get("total_cost") or 0.0
+        acc_sessions = totals.get("sessions") or 0
+        lines.append(f"  ${acc_cost:.4f} ({acc_sessions} sesiones)")
+
+        await update.message.reply_text("\n".join(lines), parse_mode=ParseMode.MARKDOWN)
+    finally:
+        await db_conn.close()
+
+
 async def cmd_process(update: Update, ctx: ContextTypes.DEFAULT_TYPE):
     if not is_authorized(update.effective_user.id):
         return
@@ -576,6 +628,7 @@ def create_bot() -> Application:
     app.add_handler(CommandHandler("generate", cmd_generate))
     app.add_handler(CommandHandler("sources", cmd_sources))
     app.add_handler(CommandHandler("outputs", cmd_outputs))
+    app.add_handler(CommandHandler("costs", cmd_costs))
     app.add_handler(CommandHandler("process", cmd_process))
     app.add_handler(CommandHandler("cancel", cmd_cancel))
     app.add_handler(CommandHandler("purge", cmd_purge))