Add KSP 2.3.11 verification metadata

[skrcode]

Companion fix for #360.

The KSP 2.3.11 update is blocked by strict Gradle dependency verification because the new plugin artifacts are not yet trusted. This adds the generated SHA-512 entries for exactly the six KSP 2.3.11 JAR/module artifacts resolved by the build:

• symbol-processing-api
• symbol-processing-common-deps
• symbol-processing-gradle-plugin

Each checksum was independently verified against the downloaded artifact. No existing trust entries were removed or weakened.

Verification:

• ./gradlew build
• BUILD SUCCESSFUL in 9m 43s
• 146 tasks completed
• xmllint --noout gradle/verification-metadata.xml
• git diff --check

[thestinger]

ll be handled as part of updating it with the standard way we generate verification metadata. We're updating most dependencies prior to releases rather than continuously doing it since there are so many updates and it would take too much time.