Write full e2e test suite covering the complete gist lifecycle

[BigBen-7]

Description

The project needs a comprehensive end-to-end test suite that proves the full gist lifecycle works: create a gist, verify it is in the database, query it by location, fetch its IPFS content, verify expiry. This is the most visible quality signal for campaign reviewers and judges.

Context

• e2e tests live in Backend/test/
• The project uses Jest and Supertest for e2e testing
• A real PostGIS test database is required — same schema, database name: gist_test
• IpfsService and SorobanService should be mocked using NestJS overrideProvider
• Run with: npm run test:e2e

Requirements

Create the following test suites:

Suite 1: POST /gists

• Creates a gist with valid payload — expects 201 with id, gist_id, tx_hash, content_cid
• Rejects missing lat — expects 400
• Rejects invalid authorAddress — expects 400
• Rejects text over 280 characters — expects 400

Suite 2: GET /gists

• Returns gists within radius of seeded coordinates
• Does NOT return gists outside the radius
• Does NOT return expired gists
• Returns results sorted by distance ascending
• Pagination cursor returns correct next page

Suite 3: GET /gists/:id

• Returns correct gist by UUID
• Returns 404 for unknown UUID
• Returns 404 for expired gist

Suite 4: GET /gists/:id/content

• Returns IPFS content for valid gist
• Returns 404 for unknown gist

Suite 5: GET /gists/count

• Returns correct count within radius
• Excludes expired gists from count

Suite 6: GET /health

• Returns status ok with 200

Files to Touch

• Backend/test/gists.e2e-spec.ts — main test file
• Backend/test/setup.ts — test database setup and teardown
• Backend/test/mocks/ipfs.service.mock.ts — mock IpfsService
• Backend/test/mocks/soroban.service.mock.ts — mock SorobanService
• Backend/test/jest-e2e.json — confirm config is correct

Acceptance Criteria

• All test suites pass with npm run test:e2e
• Tests use a real PostGIS database — not mocked
• IpfsService and SorobanService are mocked
• Tests clean up seeded data after each suite
• Minimum 20 test cases total
• No hardcoded local paths — CI-ready

Complexity: 350 points