[joeblau]

Follow-up to #74. This finishes the tsrs migration to match the org-wide plan used in sfx#75.

• Docs app: check is now next typegen && tsrs --noEmit, and it runs in prebuild before next build. next.config.mjs sets typescript.ignoreBuildErrors: true, so Next skips its slower tsc pass ("Skipping validation of types" in the build log). tsrs is pinned to exactly 0.18.0-ts7.1.0-dev.20260929.
• tsc fallback: tsrs has no Windows or Intel Mac build, so typescript stays a devDependency in both the chart package and the docs app, and Next still needs it too. The new fallback scripts are typecheck:tsc (root), typecheck / typecheck:tsc / build:ts:tsc (chart) and check:tsc (docs).

Docs type check (box, 8 vCPU, 7 interleaved cold runs, .tsbuildinfo removed each run)

	TS 6.0.3	TS 7.0.2	tsrs 0.18.0
Median	2.96 s	0.51 s	0.24 s
Peak memory	~495 MB	~260 MB	~108 MB

That's about 12x faster than tsc 6.

Gates

• Same errors: tsc 6.0.3 and tsrs report identical diagnostics on the clean docs app (0 errors) and on a deliberately broken .tsx file with 5 errors: wrong assignment, a misspelled prop, a non-ReactNode child, a bad argument and a missing required prop.
• Same output: build:ts (tsrs) and build:ts:tsc emit identical .js and .d.ts files. Only the .map mappings differ, which is the TS 6 to TS 7 source-map change covered in build: compile @bloxwap/chart with tsrs instead of tsc #74.
• Everything passes: npm run typecheck, npm run typecheck:tsc, npm run docs:build (including check-export), npm run lint and npm run coverage, which stays at 100% on all 139 rows.