ci: upload openapi-generator-cli.jar as GitHub Release asset

[sakshar2303]

## Summary
Adds a new upload-release-asset job to the Maven release workflow that
uploads openapi-generator-cli.jar as an asset to each GitHub Release tag.

Motivation

Tools like aqua (a declarative CLI version
manager) rely on GitHub Release assets to install and manage CLI tools.
Since openapi-generator-cli.jar was only published to Maven Central and not
attached to GitHub Releases, it was not possible to manage it via aqua or
similar GitHub-Releases-based version managers.

This change makes it possible to register openapi-generator-cli in the
aqua registry, following the same
pattern already established by tools like ktfmt.

Changes

• Added tags: 'v*' trigger so the workflow also runs on version tag pushes
• Changed contents permission to write in the publish job to allow
  uploading release assets
• Added a new upload-release-asset job that:
  • Runs only on tag pushes (not on every master push)
  • Builds the CLI JAR via Maven
  • Renames it to openapi-generator-cli-{version}.jar
  • Uploads it to the corresponding GitHub Release using the GitHub CLI

Related Issue

Closes #23519

---

Summary by cubic

Attach openapi-generator-cli.jar to each GitHub Release so the CLI can be installed via tools like aqua. Adds a tag-triggered job that builds and uploads the JAR as a release asset.

• New Features
  • Workflow now triggers on v* tags.
  • New upload-release-asset job runs only on tag pushes.
  • Builds and publishes openapi-generator-cli-{version}.jar to the matching GitHub Release via gh, with contents: write permission.

^{Written for commit adda3dc. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name=".github/workflows/maven-release.yml">

<violation number="1" location=".github/workflows/maven-release.yml:110">
P2: The workflow uploads an asset to a GitHub Release without ensuring the Release exists for the tag, so tag-triggered runs can fail when no Release has been created yet.</violation>
</file>

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