chore(ci): decouple check-bundle-size from @lumencast/runtime chunk names

[ClodoCapeo]

Surfaced by Vigil during the ADR 007 §B review (2026-06-04).

scripts/check-bundle-size.mjs asserts per-chunk presence (tree, status-pill, control, test, broadcast, index) that now originate from @lumencast/runtime's internal chunking (re-bundled by Vite), not Solar source. A runtime minor that renames/merges a chunk will fail CI with no Solar change.

Fix options

• Sum against a single global gz budget instead of per-named-chunk, OR
• Pin @lumencast/runtime more tightly than ^0.1.0.

priority: low. prefix chore/.

[ClodoCapeo]

IMPLEMENTATION_REPORT

Agent: Eleven
Work-unit: SOLAR-5-BUNDLE-GRAPH
Issue: #5
Commit: dfe282c (signed)
PR: #51 (draft)

Result: replaced emitted-chunk prefix assumptions with an ESM import-graph walk rooted at dist/solar.js. Mode entries are discovered from BroadcastMode/ControlMode/TestMode loader exports; renamed chunks and control/test merged chunks are counted once per mode. The broadcast guard rejects a distinct overlay mode entry while accepting an intentionally shared merged target.

Evidence:

• npm run lint: PASS
• npm run typecheck: PASS
• npm test: PASS (112 Vitest + 2 graph regression tests)
• npm run build: PASS
• npm run check:bundle: PASS — broadcast 41,254 B gz; control 43,247 B gz; test 44,813 B gz; host 143,201 B gz
• npm run test:e2e: attempted; blocked before launch because Playwright Chromium/Headless Shell executables are absent locally and CDN installation did not complete. No application assertion failed.

Remote checks: no checks are currently reported for this branch. The PR remains draft pending repository CI/review.