* docs: add SSH agent identity implementation plan
* feat(ssh): host-stamped remote foreground identity
* fix(runtime): preserve unfenced inspect call shape
* perf(ssh): traverse foreground descendants linearly
* fix(ssh): bound retired PTY evidence records
* test(ssh): cover retired incarnation retention
* fix(ssh): make remote process inspection total
* Split SSH identity build hot spots
* Fix process table snapshot module split
* test(ssh): update process inspection expectations
* docs: drop the SSH identity plan from the PR
The design doc does not belong in the product repo; it stays out of the
shipped tree while the implementation carries its own comments.
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Co-authored-by: Merge Sim <sim@local>