ci: add dependabot auto-merge workflow

[JerrettDavis]

Adds automation to enable auto-merge on Dependabot PRs once required checks pass. Not self-merging — please review.

[github-actions]

Dependency Review

The following issues were found:

• ✅ 0 vulnerable package(s)
• ✅ 0 package(s) with incompatible licenses
• ✅ 0 package(s) with invalid SPDX license definitions
• ⚠️ 1 package(s) with unknown licenses.

See the Details below.

License Issues

.github/workflows/dependabot-auto-merge.yml

Package	Version	License	Issue Type
dependabot/fetch-metadata	3.*.*	Null	Unknown License

Allowed Licenses:

MIT, Apache-2.0, BSD-2-Clause, BSD-3-Clause, ISC, 0BSD

OpenSSF Scorecard

Package	Version	Score	Details
actions/dependabot/fetch-metadata	3.*.*	🟢 8.2	Details Check Score Reason Code-Review 🟢 10 all changesets reviewed Maintained 🟢 10 30 commit(s) and 0 issue activity found in the last 90 days -- score normalized to 10 Packaging ⚠️ -1 packaging workflow not detected Binary-Artifacts 🟢 10 no binaries found in the repo Dangerous-Workflow 🟢 10 no dangerous workflow patterns detected Token-Permissions 🟢 9 detected GitHub workflow tokens with excessive permissions Pinned-Dependencies 🟢 3 dependency not pinned by hash detected -- score normalized to 3 CII-Best-Practices ⚠️ 0 no effort to earn an OpenSSF best practices badge detected Fuzzing ⚠️ 0 project is not fuzzed License 🟢 10 license file detected Signed-Releases ⚠️ -1 no releases found Branch-Protection 🟢 8 branch protection is not maximal on development and all release branches Security-Policy 🟢 10 security policy file detected SAST 🟢 10 SAST tool is run on all commits

Scanned Files

• .github/workflows/dependabot-auto-merge.yml