ci: re-run the PR-title lint on every push

[oc-tmueller]

Why

lint (workflow Lint PR title) has run on every PR in this repo since #97, but the
trigger list is [opened, edited, reopened] — synchronize was deliberately omitted, on the
grounds that a push cannot change the title.

That reasoning holds only while the check is advisory. owncloud/admin manages this repo's
docs.owncloud.com-status-checks ruleset, and required status checks are evaluated per head
sha: a check-run belongs to the commit it ran against and is never carried forward. Without
synchronize, every push leaves the new head with no lint check-run — which GitHub reads
as perpetually pending, blocking the merge until someone edits the title.

Three PRs here have already been in exactly that state, harmlessly only because the context is
not required yet:

PR	what happened	lint on the merged head?
#116	lint ran on 4c48f460 when Dependabot opened it; Dependabot then rebased to 78e0a21b	no
#110	force-pushed to a0bcc073	no
#63	pushed 5bfb225e on 2026-09-14	no

#116 is the one that matters: Dependabot never edits its own title, so had lint been required
that PR could not have been merged at all — only closed and reopened.

Evidence, for anyone re-checking:

$ gh api "repos/owncloud/docs.owncloud.com/actions/workflows/lint-pr-title.yml/runs?per_page=15" \
    --jq '.workflow_runs[] | "\(.created_at) \(.event) head=\(.head_sha[0:8]) \(.conclusion)"'
2026-09-07T10:46:39Z pull_request head=4c48f460 success   # <- #116 as opened
                                                          # <- nothing for 78e0a21b, the head that merged

What

One trigger added, plus the two comments that documented the old reasoning brought up to date:

• types: [opened, edited, reopened] → [opened, edited, reopened, synchronize]
• the comment above types: now explains that the re-run exists to re-post the check-run on the
  new sha, not to re-judge the title
• the concurrency comment now says the group is per pull request (github.ref is
  refs/pull/<n>/merge for a pull_request event), so an edit racing a push collapses to the
  newer run rather than leaving a stale red check

No change to permissions, to the pinned action
(amannn/action-semantic-pull-request@48f2562 / v6.1.1) or to the job itself.

This also aligns the repo with the rest of the org — activity, client, richdocuments,
testing and wopi all trigger on synchronize, and richdocuments is the worked example of
lint being required and the gate working.

Verification

The change is self-testing: this PR gets a second, empty commit pushed to it, and a lint
check-run must then appear on the new head sha. That result is posted as a comment below
before the PR is proposed for merge.

Follow-up

Requiring the context is a separate PR against owncloud/admin, which must merge after
this one.

Co-Authored-By: Claude Opus 5 (1M context) noreply@anthropic.com

[CLAassistant]

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[LukasHirt]

Originally approved before the second commit but seems it worked now - keeping the original approval.

[oc-tmueller]

Verification: synchronize fires, and the lint reports against the new head

The second commit on this branch is an empty one, pushed purely as the probe. Before the
change a push produced no lint run at all; now it does.

$ gh api "repos/owncloud/docs.owncloud.com/actions/workflows/lint-pr-title.yml/runs?per_page=4" \
    --jq '.workflow_runs[] | "\(.created_at) \(.event) head=\(.head_sha[0:8]) \(.status)/\(.conclusion)"'
2026-09-16T15:55:38Z pull_request head=c10aef45 completed/success   # <- the PUSHED head (this probe)
2026-09-16T15:51:51Z pull_request head=5a178307 completed/success   # <- the opened head

$ gh api repos/owncloud/docs.owncloud.com/commits/c10aef45.../check-runs --jq '[.check_runs[].name]'
["lint","build"]

Compare #116, whose merged head has no lint check-run at all:

$ gh api repos/owncloud/docs.owncloud.com/commits/78e0a21b.../check-runs \
    --jq '[.check_runs[] | "\(.name)=\(.conclusion)"]'
["build=success","deploy=skipped"]

Two details worth recording, both confirmed here:

• The trigger list is read from this PR's version of the workflow, not from main, so the
  change is self-testing — no need to merge first and hope.
• license/cla shows pending ("Contributor License Agreement is not signed yet") on this PR.
  That is the Co-Authored-By: Claude … trailer, not an unsigned human: the identical trailer
  passes on owncloud/richdocuments (#630, #633 → license/cla=success), so it is a per-repo
  cla-assistant allowlist difference, and docs(ocis): add 8.2 updates — clean-corrupt-public-shares CLI #63 hit the same thing here. It is not a required
  context on this repo today; the durable fix is to allowlist that identity for this repo the
  way richdocuments has it.