feat: v1.0.0 — UX polish, security hardening, code quality

UI/UX:
- Bill detail page tab UI (Analysis / Timeline / Votes / Notes)
- Topic tag pills on bill detail and listing pages — filtered to known
  topics, clickable, properly labelled via shared lib/topics.ts
- Notes panel always-open in Notes tab; sign-in prompt for guests
- Collapsible sidebar with icon-only mode and localStorage persistence
- Bills page defaults to has-text filter enabled
- Follow mode dropdown transparency fix
- Favicon (Landmark icon, blue background)

Security:
- Fernet encryption for ntfy passwords at rest (app/core/crypto.py)
- Separate ENCRYPTION_SECRET_KEY env var; falls back to JWT derivation
- ntfy_password no longer returned in GET response — replaced with
  ntfy_password_set: bool; NotificationSettingsUpdate type for writes
- JWT_SECRET_KEY fail-fast on startup if using default placeholder
- get_optional_user catches (JWTError, ValueError) only, not Exception

Bug fixes & code quality:
- Dashboard N+1 topic query replaced with single OR query
- notification_utils.py topic follower N+1 replaced with batch query
- Note query in bill detail page gated on token (enabled: !!token)
- search.py max_length=500 guard against oversized queries
- CollectionCreate.validate_name wired up with @field_validator
- LLM_RATE_LIMIT_RPM default raised from 10 to 50

Authored by: Jack Levy

backend/app/api/notifications.py

@@ -12,6 +12,7 @@ from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.config import settings as app_settings
+from app.core.crypto import decrypt_secret, encrypt_secret
 from app.core.dependencies import get_current_user
 from app.database import get_db
 from app.models.notification import NotificationEvent
@@ -41,7 +42,7 @@ def _prefs_to_response(prefs: dict, rss_token: str | None) -> NotificationSettin
         ntfy_auth_method=prefs.get("ntfy_auth_method", "none"),
         ntfy_token=prefs.get("ntfy_token", ""),
         ntfy_username=prefs.get("ntfy_username", ""),
-        ntfy_password=prefs.get("ntfy_password", ""),
+        ntfy_password_set=bool(decrypt_secret(prefs.get("ntfy_password", ""))),
         ntfy_enabled=prefs.get("ntfy_enabled", False),
         rss_enabled=prefs.get("rss_enabled", False),
         rss_token=rss_token,
@@ -88,7 +89,7 @@ async def update_notification_settings(
     if body.ntfy_username is not None:
         prefs["ntfy_username"] = body.ntfy_username.strip()
     if body.ntfy_password is not None:
-        prefs["ntfy_password"] = body.ntfy_password.strip()
+        prefs["ntfy_password"] = encrypt_secret(body.ntfy_password.strip())
     if body.ntfy_enabled is not None:
         prefs["ntfy_enabled"] = body.ntfy_enabled
     if body.rss_enabled is not None: