feat(core-analytics): add React provider and useAnalytics hook

Adds a ./react subpath export to @repo/core-analytics containing
<AnalyticsProvider value={IAnalytics}> and useAnalytics(): IAnalytics.
useAnalytics() throws AnalyticsContextError when called outside a provider.
React Testing Library test verifies track() flows through context using
RecordingAnalytics. Switches vitest config to pick up .tsx test files
via environmentMatchGlobs and extends tsconfig to react-library.json
for JSX support.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

coverage/summary.json

@@ -1,18 +1,18 @@
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+  "commit": "065ca1b",
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@@ -50,12 +50,12 @@
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