* feat(compaction): always rebuild the system prompt at the commit boundary — keep-prompt now gated on byte equality of the LIVE builder output; plugin sections re-render with fail-open to last good bytes
* feat(clock): 'Conversation started' resolves through the session-lineage ROOT — a compacted/rotated session keeps its original birth date (Bot Mode forever-chats know when they were first born)
* test: retire old-contract pins — plugin sections re-render at invalidate (freeze stays restore-only), commit boundary always runs the live builder, byte-equal keep preserves object identity
test_real_aiagent_builds_section_once_and_keeps_it_out_of_static_prefix
builds the system prompt twice and asserts byte equality, but the prompt
embeds build_coding_workspace_block() — live git status/log output. A git
call failing between the two builds (xdist contention in CI) makes the
Branch/Recent-commits lines differ and fails the test on unrelated PRs
(first seen on #89027's run: diff showed only '- Branch: (detached HEAD)'
and recent-commit lines).
Mechanism reproduced locally: with coding posture on and cwd inside the
checkout, failing git calls on the second build only => first != rebuilt;
with the snapshot pinned, identical git failure => byte-equal. The real
block's byte-stability is coding_context's own contract; this test is
about plugin sections.
Salvage the plugin-owned static prompt idea from PR #51589 into the constrained #64167 contract: stable IDs, deterministic placement, bounded fail-open rendering, and full-prompt resume recovery without new session columns.
Co-authored-by: Topher Ross <biz@topherross.com>
Teknium