🧪 add tests/main.rs to improve testing coverage for src/main.rs

[undivisible]

🎯 What: The testing gap for src/main.rs has been addressed by creating integration tests in tests/main.rs.
📊 Coverage: Scenarios covered include: running without arguments, using --help/-h/help, providing invalid arguments, and using an unknown command. These test the main binary command line interface, output, and standard error.
✨ Result: Enhanced test coverage for the src/main.rs logic without requiring complex refactoring of the main process structure.

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PR created automatically by Jules for task 7801213888049868669 started by @undivisible

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Note

Low Risk
Test-only addition with no production code changes.

Overview
Adds integration tests in tests/main.rs that exercise the zkr binary’s CLI argument handling.

Covers no-args and help flags printing usage text, invalid argument shapes returning the usage error JSON on stderr, and unknown commands returning an error after opening a temp DB.

^{Reviewed by Cursor Bugbot for commit 910245d. Configure here.}

[google-labs-jules]

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(requestId: serverGenReqId_1ae2a786-fd20-46cf-8d09-80e5baa5c746)

[undivisible]

Superseded by the reviewed and merged integration in #22.

[google-labs-jules]

Superseded by the reviewed and merged integration in #22.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.