[ARC/DinD] Emit chroot.binariesSourcePath and chroot.identity in AWF stdin-config (#38911)

* Initial plan

* Fix: merge chroot inject into arcDindPrefixProbe to avoid duplicate DOCKER_HOST condition

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* Address code review: explain Python compactness, use json.Marshal in test

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* docs(adr): add draft ADR-38911 for AWF chroot runtime config injection

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* chore: placeholder

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* fix: patch /tmp/gh-aw/awf-config.json in chroot inject, add error handling, fix test python check

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* chore: merge main into branch

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* Add changeset

* chore: merge main and resolve conflicts in awf_helpers.go

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

* fix: use python3, add preservation and structural test assertions

Co-authored-by: pelikhan <4175913+pelikhan@users.noreply.github.com>

* chore: merge main into branch

Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: lpcox <15877973+lpcox@users.noreply.github.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: pelikhan <4175913+pelikhan@users.noreply.github.com>
Co-authored-by: Landon Cox <landon.cox@microsoft.com>

Author: 5 people