cleanup/program-tracker: staged structural cleanup program for the merged Apple-platform repo

[PowerBeef]

Whole-repo cleanup tracker for the staged structural-cleanup program.

Chosen program shape:

• whole tracked repo in scope
• structural cleanup first, not release-proof first
• truth surfaces stay current while the public homepage freeze remains intact
• one cleanup concern per tranche
• behavior stays stable unless a correctness fix cannot be separated safely

Current tracked epics:

• cleanup/harness-tooling: finish validation-surface consolidation for the merged Apple-platform repo #16 harness and validation-surface consolidation
• cleanup/swift-structure: finish decomposing oversized app-shell and engine coordinator surfaces #17 Swift structure and coordinator decomposition
• cleanup/compat-audit: decide keep-refactor-delete for retained preview, debug, and manual-verification surfaces #18 compatibility, preview, and manual-verification audit
• cleanup/vendor-boundaries: audit retained vendor examples, media, and boundary docs for the merged runtime stack #19 vendor-boundary and retained upstream-surface audit

Tracking checklist:

• cleanup/harness-tooling: finish validation-surface consolidation for the merged Apple-platform repo #16
• cleanup/swift-structure: finish decomposing oversized app-shell and engine coordinator surfaces #17
• cleanup/compat-audit: decide keep-refactor-delete for retained preview, debug, and manual-verification surfaces #18
• cleanup/vendor-boundaries: audit retained vendor examples, media, and boundary docs for the merged runtime stack #19

Completion rule:

• this tracker closes only after the remaining cleanup epics describe the live repo shape, the maintained docs match the repo, and no major structural drift remains between code ownership and the cleanup program