chore: simplify and clean up CI workflows (#617)

- Remove redundant Gradle flags, env vars, and unused settings across
all workflows
- Minimize GitHub Actions permissions to least-privilege
- Drop Windows build matrix (JVM tests covered by Linux)
- Simplify CodeQL workflow (remove matrix, unused permissions, stale
triggers)
- Clean up gradle.properties (remove unused KMP settings)

## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->

## Breaking Changes
—

## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update

## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

.github/workflows/gradle-publish.yml

@@ -1,10 +1,3 @@
-# This workflow uses actions that are not certified by GitHub.
-# They are provided by a third-party and are governed by
-# separate terms of service, privacy policy, and support
-# documentation.
-# This workflow will build a package using Gradle and then publish it to GitHub packages when a release is created
-# For more information see: https://github.com/actions/setup-java/blob/main/docs/advanced-usage.md#Publishing-using-gradle
-
 name: Release
 
 on:
@@ -17,8 +10,7 @@ jobs:
     runs-on: macos-latest
     environment: release
     env:
-      JAVA_OPTS: "-Xmx4g -Dfile.encoding=UTF-8 -XX:MaxMetaspaceSize=768m -Djava.awt.headless=true"
-      GRADLE_OPTS: "-Dorg.gradle.daemon=false -Dkotlin.compiler.execution.strategy=in-process"
+      GRADLE_OPTS: "-Dorg.gradle.daemon=false"
 
     permissions:
       contents: write
@@ -35,21 +27,8 @@ jobs:
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v5
 
-      - name: Clean Build with Gradle
-        run: ./gradlew clean build -x :conformance-test:test --rerun-tasks --max-workers 2 --continue --configure-on-demand --parallel
-
-      - name: Publish Test Report
-        uses: mikepenz/action-junit-report@v6
-        if: ${{ !cancelled() }}
-        with:
-          annotate_only: true
-          detailed_summary: true
-          flaky_summary: true
-          group_suite: true
-          include_empty_in_summary: false
-          include_time_in_summary: true
-          report_paths: '**/test-results/**/TEST-*.xml'
-          truncate_stack_traces: false
+      - name: Build
+        run: ./gradlew build --rerun-tasks --max-workers 2 --continue
 
       - name: Publish to Maven Central Portal
         id: publish