Split the monolithic index.ts into routers, middleware, and stores

[mikewheeleer]

Refactor the monolithic index.ts into modular Express routers

Description

The entire application — middleware, every route, all in-memory stores, and the error handler — lives in a single ~600-line src/index.ts. This makes the file hard to test in isolation and to extend. This issue decomposes it into Express Router modules, middleware modules, and store modules, while keeping the default-exported app and all current behavior identical.

Requirements and context

• Repository scope: StableRoute-Org/Stableroute-backend only.
• Create src/routes/ (e.g. pairs.ts, quote.ts, webhooks.ts, apiKeys.ts, admin.ts, meta.ts), src/middleware/ (rate limit, request id, security headers, timing, pause), and src/stores/ for the in-memory maps.
• Keep src/index.ts as the composition root that mounts routers and exports app.
• Preserve every route path, status code, and JSON body exactly so existing tests pass unchanged.
• No behavior change — this is a pure structural refactor.

Suggested execution

• Fork the repo and create a branch
• git checkout -b refactor/architecture-13-modular-routers
• Implement changes
  • Write code in: create the new modules under src/routes/, src/middleware/, src/stores/; trim src/index.ts to composition.
  • Write comprehensive tests in: src/__tests__/index.test.ts must still pass; add focused unit tests per router module.
  • Add documentation: add a module map to README.md.
  • Add TSDoc on each exported router/middleware.
  • Validate security: confirm middleware ordering (pause → rate limit → timing → headers → request id) is preserved.
• Test and commit

Test and commit

• Run npm run build, npm run lint, and npm test.
• Cover edge cases: middleware order regression, route mounting, 404 fallback still last.
• Paste full npm test output in the PR.

Example commit message

refactor: split index.ts into routers, middleware, and stores

Guidelines

• Minimum 95 percent test coverage for impacted code.
• Clear, reviewer-focused documentation.
• Timeframe: 96 hours.

Community & contribution rewards

• 💬 Join the StableRoute community on Discord for questions, reviews, and faster merges: https://discord.gg/37aCpusvx
• ⭐ This is a GrantFox OSS / Official Campaign task and may be rewarded. When your PR is merged you'll be prompted to rate the project — if this issue and the maintainers helped you ship, we'd be grateful for a 5-star rating. Clear questions in Discord and tidy, well-tested PRs are the fastest path to a merge and a reward.

[Senorespecial]

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