fix: prevent memory leak from process event listeners

[aadityakumarsah]

This PR fixes a MaxListenersExceededWarning caused by repeatedly registering process.on listeners in startServer across tests. It uses a module-level variable to ensure they are added only once.

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Note

Low Risk
Small control-flow change around existing logging handlers; no new behavior on first boot and no auth or data-path impact.

Overview
Fixes listener accumulation when startServer runs multiple times in the same Node process (e.g. repeated test runs), which triggered MaxListenersExceededWarning.

Global unhandledRejection and uncaughtException handlers are now registered behind a module-level globalProcessListenersRegistered guard so they attach once; later startServer calls skip re-registration. Handler behavior is unchanged.

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[omegascorp]

Looks good