Add TypeScript/JavaScript API route miner (#130)

[Dimwiddle]

Description

Add TypeScriptRouteMiner to discover API routes in TypeScript/JavaScript code for:

• Express member-call routes (app/router + HTTP methods)
• Next.js App Router file-based routes from app/**/route.ts|route.js with named HTTP exports

The change also wires the miner into default pipeline registration, adds focused unit coverage, and updates discovery feature scenarios/acceptance notes.

Type of Change

• New feature
• Tests
• Documentation update

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Testing

• make lint-fix ✅
• make lint ✅
• make test ✅ (490 passed)
• make pre-commit ✅

Related Issues

Closes #130