ce-ideate / ce-brainstorm: ideation HTML lands untracked in docs/ideation with no stated lifecycle

Observation

ce-ideate (SKILL.md: "a ranked ideation artifact is written to <root>/ideation/ when that root is present, else to a CE temp dir") and ce-brainstorm write their HTML output to <root>/ideation/<date>-<slug>-ideation.html, which resolves to docs/ideation/ inside the user's repository whenever a docs root exists. On my machine that left untracked HTML files sitting in four separate repos (git status --porcelain --untracked-files=all | grep docs/ideation), because the file lands in a tracked docs/ tree but nothing tracks or ignores it, and the skill does not say what should happen to it afterwards.

ce-plan (docs/plans, committed via PR) and ce-compound (docs/solutions, committed) are durable outputs and fit docs/. The ideation HTML is a one-time read for the person who ran the skill, which is a different lifecycle: it should either be gitignored by convention or written somewhere that dies with the work.

Suggestion

One of:

1. Write ideation HTML under a gitignored location the plugin owns (for example .claude/deliverables/ce-ideate/ or the plugin's existing tmp/compound-engineering-<uid>/ space used by ce-prototype), and print the path.
2. Keep docs/ideation/ but add it to the repo's .gitignore on first write (with a one-line note in the skill about why), so a read-once artifact never shows up as an untracked file in git status.
3. At minimum, document the intended lifecycle in the skill text: is the file meant to be committed, deleted after reading, or left?

Context: I maintain a harness-wide rule for this on my side (a gitignored <repo>/.claude/deliverables/<skill>/ tier plus a cross-platform opener), and the plugin's ideation output is the one producer I could not align locally because the skill text lives in the auto-updated plugin cache.

Version observed: compound-engineering 3.23.3 (every-marketplace).