docs: remove reapplication-plan.md

[hannesrudolph]

Summary

Remove the outdated docs/reapplication-plan.md document (372 lines).

Changes

• Delete docs/reapplication-plan.md

[roomote]

Rooviewer   See task

No issues found. Clean deletion of an outdated internal document (docs/reapplication-plan.md) with no references elsewhere in the codebase.

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