feat: enhance daily API tracker to auto-create issues on upstream changes

[simbo1905]

Summary

The daily API tracker workflow runs successfully but doesn't notify anyone when upstream API differences are detected. The if: failure() condition never triggers because the tracker exits 0 even when differences exist.

Current Behavior

• Tracker compares local vs upstream APIs
• Outputs JSON report to logs
• Always exits 0 (success)
• No issue created, no notification

Desired Behavior

• When differences are detected, automatically create a GitHub issue
• Deduplicate issues using SHA256 fingerprint of the diff (first 7 chars in title)
• Include terse summary in issue body
• Attach full JSON report as artifact
• Skip issue creation if matching fingerprint issue already exists (prevents spam if maintainer is busy)

Acceptance Criteria

• Tracker generates SHA256 fingerprint from differences JSON
• Workflow checks for existing issue with hash:XXXXXXX in title
• Creates new issue only if no matching fingerprint found
• Issue body contains human-readable summary of changes
• Full JSON report uploaded as workflow artifact
• Works on both Java 24 and Java 25