Add sampled Lang Core system prompt telemetry

[zahlekhan]

Summary

• add 10% sampled telemetry for successful server-side generateSystemPrompt() calls
• report allowlisted runtime metadata, component and tool counts, and locally hashed configuration and project identifiers
• exclude browser environments and avoid sending prompts, generated output, credentials, or raw component and tool definitions
• support OPENUI_TELEMETRY_DISABLED=1 and DO_NOT_TRACK=1 opt-outs
• document the telemetry behavior in the Lang Core README

Implementation

• telemetry runs asynchronously and never affects prompt generation
• project identity uses Git origin, REPOSITORY_URL, or the working directory and is cached once per runtime
• Lang Core version is injected from the package version during the build
• delivery errors and unsupported runtime capabilities are ignored

Validation

• pnpm --filter @openuidev/lang-core test (76 tests)
• pnpm --filter @openuidev/lang-core typecheck
• pnpm --filter @openuidev/lang-core run ci
• pnpm --filter @openuidev/lang-core build

[vercel]

@zahlekhan is attempting to deploy a commit to the thesys-devs Team on Vercel.

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