Bug:
ContentActions.evidence() hard-coded files_changed=[] and diffed
against HEAD~1 instead of the branch's parent. QA's _build_qa_claim_
evidence (and doc/_impl mirrors) sourced files_changed from
work_session.files_modified, which the gateway commit() never
populates (no add_files_modified plumbing). Result: QA / docs / PM
reviewers saw an empty change list on real PRs and only the latest
commit's delta — flagged in smoke-9 when PR #20 showed the README
change on GitHub but evidence() reported empty.
Fix:
Added GitService.list_changed_files (git diff --name-only against
parent branch). evidence(), _build_qa_claim_evidence,
_claim_doc_evidence, and _build_i_am_done_ok all source files_changed
from this — git is the authoritative source. evidence() also drops
the HEAD~1 base so the diff is the full PR.
Wired EvidenceRepo into ContentActionsDeps so evidence() returns
journal_highlights too, matching the QA/doc shape.