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/schemas/schemas.py

@@ -1,7 +1,7 @@
 from datetime import date, datetime
 from typing import Any, Generic, Optional, TypeVar
 
-from pydantic import BaseModel
+from pydantic import BaseModel, field_validator
 
 
 # ── Notifications ──────────────────────────────────────────────────────────────
@@ -31,7 +31,7 @@ class NotificationSettingsResponse(BaseModel):
     ntfy_auth_method: str = "none"  # none | token | basic
     ntfy_token: str = ""
     ntfy_username: str = ""
-    ntfy_password: str = ""
+    ntfy_password_set: bool = False
     ntfy_enabled: bool = False
     rss_enabled: bool = False
     rss_token: Optional[str] = None
@@ -315,11 +315,13 @@ class CollectionCreate(BaseModel):
     name: str
     is_public: bool = False
 
-    def validate_name(self) -> str:
-        name = self.name.strip()
-        if not 1 <= len(name) <= 100:
+    @field_validator("name")
+    @classmethod
+    def validate_name(cls, v: str) -> str:
+        v = v.strip()
+        if not 1 <= len(v) <= 100:
             raise ValueError("name must be 1–100 characters")
-        return name
+        return v
 
 
 class CollectionUpdate(BaseModel):