Add a `_runfiles_enabled` marker file to runfiles trees - #30674

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fmeum wants to merge 2 commits into

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fmeum:runfiles-enabled-marker

Commits on Aug 13, 2026

Detect a materialized runfiles directory via `_repo_mapping`
fmeum
committed
7c1d64a
Don't let a runfiles tree of copies go stale
fmeum
committed
1743eae