chore(ci): bump socket-registry refs to eb53b17d

[John-David Dalton (jdalton)]

Summary

• Bump socket-registry action/workflow refs from b86b2cb to eb53b17d
• Aligns with new reusable workflow defaults across all socket-* repos

Test plan

• CI passes with updated refs

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Note

Low Risk
Workflow-only changes (action pin updates and a config removal) with no runtime code impact; main risk is CI/publish behavior changes if the new pinned action commit behaves differently.

Overview
Updates GitHub Actions workflows (CI, publish/provenance, and weekly dependency updates) to pin SocketDev socket-registry reusable actions to commit eb53b17d instead of b86b2cb.

Removes .github/dependabot.yml, eliminating the repository’s previously disabled Dependabot configuration file.

^{Reviewed by Cursor Bugbot for commit ef89301. Configure here.}

[John-David Dalton (jdalton)]

Superseded by #1207 which already bumped to bbe46386.