[changelog] Add changelog for java/v1.0.9

[github-actions]

Caution

Protected files were modified in this change.
This pull request is in request_review mode and requires explicit human scrutiny before merge.

Protected files: CHANGELOG.md

Adds the java/v1.0.9 entry to CHANGELOG.md with 2 highlighted features and 9 other changes spanning Java-specific improvements and cross-SDK updates that landed in this release.

Highlighted features:

• userPromptTransformed hook via SessionHooks.setOnUserPromptTransformed
• Custom JSON schema override for @CopilotToolParam + compile-time blank-description enforcement

Other changes (9): disabled MCP servers, agentStop hook, GitHubMcpToolConfig, managed approval on permissions, enableExperimentalMode, additional directories, customAgentsLocalOnly forwarding, ReasoningEffort.max, and version-script bugfix.

Generated by Release Changelog Generator · sonnet46 70.5 AIC · ⌖ 9.03 AIC · ⊞ 8.6K · ◷

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Note

This was originally intended as a pull request, but the git push operation failed.

Original error: pushSignedCommits: refusing unsigned push for branch 'changelog/java-v1.0.9-0adf9c759a4da870': Signed-commit payload violates file-protection policy (request_review): CHANGELOG.md

Workflow Run: View run details and download bundle artifact

The bundle file is available in the agent artifact in the workflow run linked above.

To create a pull request with the changes:

# Download the artifact from the workflow run
gh run download 31060734155 -n agent -D /tmp/agent-31060734155

# Fetch the bundle into a temporary ref, then update the local branch
git fetch /tmp/agent-31060734155/aw-changelog-java-v1.0.9.bundle refs/heads/changelog/java-v1.0.9:refs/bundles/create-pr-changelog-java-v1-0-9-0adf9c759a4da870-3276e03d
git update-ref refs/heads/changelog/java-v1.0.9-0adf9c759a4da870 refs/bundles/create-pr-changelog-java-v1-0-9-0adf9c759a4da870-3276e03d
git checkout changelog/java-v1.0.9-0adf9c759a4da870
# Ensure the working tree matches the updated branch
git reset --hard
# Remove the temporary bundle ref
git update-ref -d refs/bundles/create-pr-changelog-java-v1-0-9-0adf9c759a4da870-3276e03d

# Push the branch to origin
git push origin changelog/java-v1.0.9-0adf9c759a4da870

# Create the pull request
gh pr create --title '[changelog] Add changelog for java/v1.0.9' --base main --head changelog/java-v1.0.9-0adf9c759a4da870 --repo github/copilot-sdk