Add load-order validation script to catch missing or misordered script tags

[zntznt]

Problem

index.html loads 17 scripts in strict dependency order. A misordered <script> tag causes silent failures (classes undefined, mixins load before App exists). There's no automated check. The CLI (cli.js) and test runner (test/run.js) replicate the load order manually — if a file is added to js/ but not to these lists, it's silently excluded.

Plan

Add a small Node script scripts/check-load-order.js that:

1. Parses <script src="js/..."> tags from index.html in order
2. Lists all js/*.js files on disk
3. Reports:
   • Files on disk NOT in index.html (unused or forgotten)
   • Files in index.html NOT on disk (broken links)
   • Mixin scripts that come before app.js (load-order violation)
   • Duplicate <script> tags

Run as a pre-test or CI step:

node scripts/check-load-order.js
# Exit 1 if violations found

Effort

~1 hour. New file only. ~40 lines of Node.js.

[zntznt]

Implementation Order

This is Phase 3 · Step 3.1 — implement after Phase 2.

Priority: MODERATE
Phase: 3 (Structural / Developer-Facing)
Order: 7 of 10
Depends on: Nothing
Effort: ~1 hour