fix(api): propagate database errors correctly in local-coding stats endpoint

[ArshVermaGit]

Description

This PR addresses a silent failure issue in the backend where critical database connection or query errors were being intentionally swallowed by the API.

Previously, the /api/local-coding/stats route caught database query failures (e.g., if the Supabase instance was down or unreachable) and "gracefully degraded" by returning an empty, mock data object alongside a 200 OK status. This masked underlying infrastructure issues, broke frontend error handling (since the fetch API assumed success), and made debugging significantly more difficult.

Resolved Issue

Resolves #1792

Changes Made

• Error Propagation: Removed the fallback mechanism in src/app/api/local-coding/stats/route.ts. The endpoint now correctly catches database errors, logs them to the server console, and halts execution by returning a standard 500 Internal Server Error status with an appropriate error message.

Impact

• Observability: Backend database failures are now immediately visible to the frontend, enabling proper fallback states, retry logic, or user-facing error messages instead of displaying mysteriously empty charts.

Testing

• Ran the unit test suite (npm run test test/local-coding-stats.test.ts).
• Verified that the test asserting the endpoint "returns 500 when Supabase fails instead of hiding the error as empty stats" now completely passes.

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[ArshVermaGit]

Hi @Priyanshu-byte-coder ! Issue #1792 has been resolved. Please review the PR and merge it under GSSoC. Thanks!