Fix Windows sidecar initialization exiting early during beforeDevCommand

[sameerthawait]

Summary

Fixes a Windows-specific issue where prepare-sidecar.mjs exited early
during Tauri beforeDevCommand, causing sidecar initialization to be
incomplete.

Root Cause

On Windows, calling process.exit(0) inside beforeDevCommand can cause
Tauri to treat the command as failed, preventing the sidecar from being
ready on first launch.

Fix

Removed the early process.exit(0) and allowed the script to complete
naturally, ensuring proper sidecar setup.

Verification

• prepare-sidecar.mjs completes successfully on Windows
• beforeDevCommand no longer fails
• Sidecar is correctly detected on first launch

Fixes #270

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

[sameerthawait]

Thanks! Happy to make any changes if needed.