[Hard]: Improve subgraph relationships and pagination-ready frontend queries

### Context and Motivation

Current data model works but can be improved with clearer relationships and scalable query strategy for future growth.

### Architecture Proposal

Extend schema relationships where appropriate.
Update mappings to maintain new relationships.
Regenerate subgraph types.
Update frontend query layer for pagination-friendly access.
Validate rendering remains stable.

### Cross-Repo Scope

event-ticketinng/schema.graphql
event-ticketinng/src/event-ticketing.ts
event-dappp/src/graphql/queries.js
event-dappp/src/App.js

### Acceptance Criteria

- [ ] Schema includes clearer entity relationships where needed
- [ ] Subgraph types regenerate and build succeeds
- [ ] Frontend query flow supports pagination-style fetching
- [ ] Existing pages continue to render correctly

### Verification and Test Strategy

Run graph codegen and graph build.
Run frontend and verify events/tickets render correctly.
Validate pagination behavior if added.

### Dependencies or Blockers

Requires careful schema migration handling.
Query changes may require UI adjustments.

Start by reading event-ticketinng/schema.graphql and src/event-ticketing.ts to identify the intended relationship and mapping changes, then inspect event-dappp/src/graphql/queries.js and App.js for the current query and rendering flow. Run graph codegen and graph build before checking the frontend; done means pagination-style fetching works and events and tickets still render correctly.

Written by the indexing model from the issue text.