fix(connect): add missing randomBytes import and rename parseGoogleState to parseOAuthState

[MehtabSandhu11]

Summary

Two bugs were present in apps/backend/src/routes/connect.ts. First, generateState()
called randomBytes from Node's crypto module without ever importing it, meaning any
request to GET /connect/github would throw a ReferenceError: randomBytes is not defined at runtime and crash the entire GitHub connect flow. Second, the helper
function responsible for decoding the OAuth state in the GitHub callback was named
parseGoogleState despite Google connect not existing anywhere in this file — a
misleading name that could confuse any developer maintaining or extending this code.
Both issues are fixed in this PR with minimal, targeted changes.

Closes #178

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Type of Change

• Bug fix
• New feature
• Refactor (no functional change)
• UI / Design change
• Tests only
• Documentation
• Infrastructure / DevOps
• Security

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What Changed

• apps/backend/src/routes/connect.ts — added import { randomBytes } from 'crypto'
  at the top of the file so generateState() no longer throws a ReferenceError at
  runtime on any GET /connect/github request.
• apps/backend/src/routes/connect.ts — renamed parseGoogleState to
  parseOAuthState at both its declaration (line 158) and its single call site
  (line 64) inside the /github/callback handler to accurately reflect its purpose.

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How to Test

1. Before this fix: call GET /connect/github with a valid auth token — confirm it
   previously crashed with ReferenceError: randomBytes is not defined.
2. After this fix: call GET /connect/github with a valid auth token — confirm it
   redirects to GitHub's OAuth page without errors.
3. Complete the full GitHub connect flow end-to-end — confirm the callback decodes
   the state correctly and stores the token successfully.
4. Search the codebase for parseGoogleState — confirm no references remain.

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Checklist

• My code follows the project's coding style (pnpm -r run lint passes).
• TypeScript compiles without errors (pnpm -r run typecheck).
• I have added or updated tests for the changes I made.
• All tests pass locally (pnpm -r run test).
• I have updated documentation where necessary.
• No new console.log or debug statements left in the code.
• Breaking changes are documented in this PR description.

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Screenshots / Recordings

N/A — backend bug fix with no UI changes.

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Additional Context

The rename from parseGoogleState to parseOAuthState is a non-breaking change —
the function is private to this module (not exported) and has exactly one call site,
which is updated in the same commit. No other files reference this function. The
randomBytes import is the more critical of the two fixes since it represents a
guaranteed runtime crash on every connect attempt — the rename is a correctness and
maintainability fix on top of that.

Please add the appropriate labels so that I can get GSSoC points.

[ShantKhatri]

LGTM.