[maintenance] migrate deps to libs.versions.toml

[pq]

Fixes: #8921.

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[gemini-code-assist]

Code Review

This pull request migrates the project to use a Gradle version catalog (libs.versions.toml), replacing hardcoded dependency and plugin declarations in build.gradle.kts with centralized references. Feedback includes a requirement to add a mandatory copyright header to the new version catalog file, as well as suggestions to improve the organization of Guava dependency versions by using specific version references instead of hardcoded strings within the catalog.