feat: add per-pool notification muting (#146)

[Francis6-git]

Description:
Implemented per-pool notification muting end-to-end (DB → UI toggle → Edge Function email sending).

Changes made:

1. Database: store per-pool mute state

• Added migration: supabase/migrations/20260629010000_add_muted_pools_to_user_profiles.sql
• Adds user_profiles.muted_pools JSONB NOT NULL DEFAULT '[]'::jsonb

2. Edge Function: respect muted pools when sending emails
   Updated: supabase/functions/notify-pool-event/index.ts

• Fetches muted_pools alongside global notification_preferences
• When sending email to a recipient:
• If recipientProfile.muted_pools contains the event pool_id, skip sending email for that pool
• In-app notifications inserts are unchanged (still written for all recipients)

3. Frontend model + API payload support
   Updated: frontend/hooks/useUserProfile.ts

• Added muted_pools: string[]
• Defaulting logic uses muted_pools: []
• saveProfile typing now allows updating muted_pools

Updated: frontend/app/api/user-profile/route.ts

• GET now selects muted_pools
• POST already upserts ...updates, so it persists muted_pools automatically

4. UI: add toggle on the group detail page
   Created: frontend/components/group/GroupMuteNotificationsToggle.tsx

• Renders a “Mute notifications for this pool” button
• Uses useUserProfile(address) and toggles membership in muted_pools
• Updated: frontend/components/group/group-details.tsx
• Imports and renders

Files touched/added:

• Added: supabase/migrations/20260629010000_add_muted_pools_to_user_profiles.sql
• Updated: supabase/functions/notify-pool-event/index.ts
• Updated: frontend/hooks/useUserProfile.ts
• Updated: frontend/app/api/user-profile/route.ts
• Added: frontend/components/group/GroupMuteNotificationsToggle.tsx
• Updated: frontend/components/group/group-details.tsx

Acceptance Criteria coverage:

• Muting stops email notifications for that pool only (Edge Function checks muted_pools per recipient + pool_id)
• Toggle persists (saved into user_profiles.muted_pools)
• Additive with global preferences (mute is checked in addition to existing notification_preferences gating)

Closes #146

[Sendi0011]

Great implementations @Francis6-git