[DEVEX1] Generate TanStack hooks for new APIs; replace direct fetches

[zhn1010]

Priority: Med
Type: Implementation
Est: 1h
Original Ref: DEVEX1

Dependencies

• [QL-API1] Proposed answer create API (validation, auth) #74
• [QL-API2] Link create/list APIs (targeted/broadcast, restriction rules, relationshipStrength) #76
• [MQ-API1] Leads list/decision API (list, accept/reject, auth) #85
• [MQ-API2] Chat list API per quest/lead #87
• [N3] Backend unread count/list + mark-read mutation #101
• [GC2] Gift card purchase/claim API + validation #104