feat: UX improvements — secure webhooks, locale fixes, dynamic languages, UI polish

- Remove top paginator from dashboard events, keep only bottom
- Fix test message locale: pass UI locale to email/matrix bot tests
- Convert webhook auth mode from text input to icon grid selector
- Generate secure UUID tokens for webhook URLs instead of sequential IDs
- Move Recent Payloads into per-provider expandable container (lazy-loaded)
- Make template config languages dynamic via app settings instead of hardcoded
- Change default dev port to 5175

packages/server/src/notify_bridge_server/api/email_bots.py

@@ -2,7 +2,7 @@
 
 import logging
 
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, Query, status
 from pydantic import BaseModel
 from sqlmodel import select
 from sqlmodel.ext.asyncio.session import AsyncSession
@@ -117,12 +117,16 @@ async def delete_email_bot(
 @router.post("/{bot_id}/test")
 async def test_email_bot(
     bot_id: int,
+    locale: str = Query("en"),
     user: User = Depends(get_current_user),
     session: AsyncSession = Depends(get_session),
 ):
     """Send a test email to the bot's own address to verify SMTP connection."""
     bot = await _get_user_bot(session, bot_id, user.id)
 
+    from ..services.notifier import _get_test_message
+    msg = _get_test_message(locale, "email")
+
     from notify_bridge_core.notifications.email.client import EmailClient, SmtpConfig
     client = EmailClient(SmtpConfig(
         host=bot.smtp_host,
@@ -135,8 +139,8 @@ async def test_email_bot(
     ))
     result = await client.send(
         to_email=bot.email,
-        subject="Notify Bridge — Test Connection",
-        body_text="This is a test email from Notify Bridge. Your SMTP settings are working correctly.",
+        subject=f"Notify Bridge — {msg}",
+        body_text=msg,
     )
     return result