fix: bound InMemoryCache default size to prevent unbounded heap growth

[marceltft]

The default cache value was previously -1 (unbounded), meaning every jar, Kotlin capability, and annotation processor analyzed during a build was retained for the lifetime of the build service. On large builds this is a significant and unbounded source of heap pressure. Default to a bounded size (300) instead.

Context

With a big mono repo with lots of projects, this is causing OOM.

Contributor Checklist

• [ x ] I have read the Contributing guide.
• [ x ] I have read the Code of Conduct.
• [ x ] No part of this pull request was created with an LLM/AI.
• [ x ] All contributed code can be distributed under the terms of the Apache License 2.0, e.g. the code was written by yourself or the original code is licensed under a license compatible to Apache License 2.0.
• [ x ] Check "Allow edit from maintainers" option in pull request so that additional changes can be pushed by project maintainers.
• [ x ] Provide functional tests (under src/functionalTest) to verify changes from a user perspective.
• [ x ] Provide unit tests (under src/test) to verify logic.
• [ x ] Ensure that unit tests pass: ./gradlew test.
• [ x ] Ensure that functional tests pass: ./gradlew :functionalTest -DfuncTest.quick.