Upgrade TypeScript to 7 (build failing — needs review)

[woksin]

Summary

Upgrades the Components repo to TypeScript 7.0.2 — the new native (Go) compiler that is now latest on npm. The tsc CLI typecheck/build passes cleanly, but the broader JavaScript toolchain (ESLint typed-linting and Rollup bundling) is not yet compatible with the native compiler, so CI and publish will fail until those tools add native-compiler support. See the blocker section below.

Changed

• typescript: ^6.0.3 → ^7.0.2 (root package.json, the only manifest declaring typescript).
• Yarn: 4.5.3 → 4.17.1 (packageManager + .yarnrc.yml yarnPath + .yarn/releases/). Required: Yarn 4.5.3's bundled plugin-compat tried to apply its built-in TypeScript patch to lib/_tsc.js, which the native TS7 package no longer ships, aborting yarn install. Yarn 4.17.1 handles the native package and installs cleanly.
• tsconfig.json / Source/tsconfig.json: removed compiler options that TS7 has removed (hard TS5102 errors otherwise): baseUrl (root + Source), downlevelIteration, and the now-unnecessary ignoreDeprecations: "6.0". No baseUrl-rooted imports exist in the source (all non-relative imports are real npm packages), so this is a safe no-op for resolution.

Package manager

Yarn (workspaces; Source builds, ESLint is test-only). No lockfile is committed in this repo, per its existing convention. yarn install succeeds under 4.17.1.

Verification

• typescript resolves to 7.0.2 (require('typescript').version → 7.0.2, tsc --version → Version 7.0.2).
• yarn build (per-workspace tsc -p tsconfig.json) — PASSES, exit 0. tsc -b on Source typechecks and emits dist/esm (.js + .d.ts + maps) with zero errors.

⚠️ Blocker — native compiler has no programmatic JS API

TS7's typescript npm package exposes only version and versionMajorMinor from its JS module — the classic compiler API (ModuleKind, ScriptTarget, createProgram, …) is undefined. The native compiler is a Go binary driven through the tsc CLI. Any tool that loads typescript as a library therefore breaks:

• ESLint typed-linting (yarn lint / yarn ci): @typescript-eslint/typescript-estree crashes with TypeError: Cannot read properties of undefined (reading 'Cjs') (ts.ModuleKind.Cjs).
• Rollup bundling (g:build / prepare, i.e. the CJS bundle for npm publish): @rollup/plugin-typescript crashes with TypeError: Cannot read properties of undefined (reading 'ES2015') (ts.ModuleKind.ES2015).

Because CI's javascript-build.yml runs yarn ci (which includes the lint step) and publish.yml produces the Rollup bundle, both will fail until @typescript-eslint and @rollup/plugin-typescript ship native-compiler support (or the project moves those steps off the classic TS API). This is an upstream ecosystem gap, not a config error, and is out of scope for a version bump — hence the bump is kept and flagged for review. Vitest (esbuild-based transforms) is likely unaffected but was not exercised here.

Workflow changes

None required. Grepping .github/workflows/ found no explicit typescript version pins or tsc-install steps — the only build reference is yarn build in publish.yml. No workflow files were modified.

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