[META] Reduce repo size

[willingc]

Currently, the repo exceeds a reasonable size for github actions and cloning takes a loooong time.

• Run analysis to reduce repo size #439
• Remove stale branches from repo #438

Related to #313

Artifacts warning in GitHub Action: Warning: Uploaded artifact size of 3094501959 bytes exceeds the allowed size of 1 GB. Deployment might fail.

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Plan

1. Initial step: Analysis
2. Determine options
3. Discuss options among core team
4. Select a reasonable next action to reduce size