feat: add support for Pub/Sub emulator configuration

[jusemon]

Add Pub/Sub Emulator Support

Implements support for the Google Cloud Pub/Sub emulator based on feedback from #381. This PR addresses the feature request in #290 with a cleaner boolean configuration approach.

Changes

• Added cps.useEmulator config (defaults to false)
• Respects PUBSUB_EMULATOR_HOST environment variable
• Falls back to cps.endpoint if env var not set
• Uses proper emulator connection setup (no credentials, plaintext)
• Updated README documentation
• Added unit tests

Usage

cps.useEmulator=true
cps.endpoint=localhost:8085  # optional

All tests pass (81 tests, 0 failures). Fixes #290 ☕️

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[jusemon]

Hi @matt-kwong, could you help me review this one? I have been using in for our local development successfully, the connector is also used in prod, no issues neither.

Thank you!

[matt-kwong]

Thanks for addressing the feedback from the other PR!

Aside from my formatting comments, could you also address the build and formatting errors in the PR checks?

[jusemon]

Thanks for addressing the feedback from the other PR!

Aside from my formatting comments, could you also address the build and formatting errors in the PR checks?

Hi @matt-kwong, all comments has been addressed