fix: show progress message in ujust update bootc fallback

[Copilot]

bluefin-common PR

What does this change?

ujust update no longer appears hung in the non-bctl path: it now prints a clear progress message before bootc upgrade starts layer download/apply work.

Why?

Users reported that ujust update could sit silently during image fetch, creating a false “stuck” signal despite normal update progress.

• Fallback UX (no bctl)
  • Add one explicit status line immediately before sudo bootc upgrade in system_files/shared/usr/share/ublue-os/just/update.just.
• Regression coverage
  • Extend tests/test_update_just.bats to assert the fallback path emits the new progress line.

echo "Starting OS image update (this may take a while as layers download)..."
sudo bootc upgrade

PR pipeline

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Checklist

• PR title follows Conventional Commits (fix:, feat:, docs:, ci:, refactor:, etc.)
• just check passes
• pre-commit run --all-files passes
• Skill doc updated if the change affects agent-facing conventions or behavior (see docs/skills/skill-improvement.md)
• AGENTS.md / docs/SKILL.md / docs/skills/ links remain valid
• CI is green after push: gh run list --repo projectbluefin/common --limit 5

AI attribution

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Assisted-by: GPT-5 via GitHub Copilot
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Original prompt

Fix #897: ujust update does not show any progression

Read the issue in full, including every comment, before changing anything.
Reproduce the reported behaviour first and say how you reproduced it. If you
cannot reproduce it, say so plainly and stop rather than guessing at a fix.

Read AGENTS.md and CONTRIBUTING.md in this repository and follow them. This is
a toil-reduction change for an under-maintained project: repair what is broken
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Reference the issue number in the pull request body.

[castrojo]

LGTM. Minimal, correct fix for #897's non-bctl path:

• echo "Starting OS image update (this may take a while as layers download)..." is placed immediately before sudo bootc upgrade in the fallback branch, after the bctl early-exec — so bctl users (who already get a progress UI) are unaffected.
• The bats assertion [[ "${output}" == *"Starting OS image update"* ]] is added to the existing no-layered-packages test, which is the exact path that exercises the fallback. Correct scope, no new surface.

CI: the validate failure is stale — it ran when the title was [WIP] Fix ujust update not showing progression and failed the Conventional Commits title check. The title has since been fixed to fix: show progress message in ujust update bootc fallback; a re-run should pass. All other checks (test, builds, E2E GNOME 50) are green.

Note: the follow-up comment on #897 about a spurious "staged — reboot when ready" notification is a separate regression and correctly out of scope here.

[hanthor]

Approving — one echo, right place, correct branch.

The placement is specifically after the exec bctl update hand-off, so it only fires on the path that actually lacks a progress UI. That's the correct branch: bctl users already get the richer output and would otherwise see a redundant line before being exec'd away.

Two small notes, neither blocking:

• The message lands before sudo bootc upgrade, so on a machine without a cached sudo timestamp the user sees "Starting OS image update…" and then a password prompt. That ordering is still an improvement over silence, and it becomes moot if #932 lands a NOPASSWD rule for bootc upgrade.
• tests/test_update_just.bats currently has 4 pre-existing failures on main (independently observed and called out in #942). Your added assertion isn't among them, but if CI on this PR shows that file red, that's the cause rather than this change.

Worth noting the fix doesn't make bootc upgrade itself chattier — it just closes the silent window before bootc starts emitting its own progress, which is the window #897 actually described.