Enhance /status with health indicators, stale detection, team mode, and quick wins

[sebastientaggart]

Enhance the /status skill with seven improvements that surface actionable context without clicking through GitHub:

1. PR health indicators — CI check status and review decision badges on every open PR
2. Stale work detection — configurable STALE_DAYS threshold (default 14) flags forgotten work
3. Team mode (--team) — aggregate view of all open work grouped by person, for standups
4. Draft PR indicator — [draft] badge distinguishes drafts from published PRs
5. Summary counts line — scannable one-liner at the top of personal mode output
6. Needs your review — new section showing PRs awaiting your review (personal mode, @me only)
7. Merge conflict indicator — ⚠️ conflicts badge on PRs that can't merge cleanly

Also adds STALE_DAYS to config schema and updates documentation.

Issue #106

[sebastientaggart]

Review Summary

Verdict: APPROVE

Findings

No issues found. Code looks correct and follows project conventions.

Details reviewed:

• All seven features described in the PR body (health badges, stale detection, team mode, draft indicator, summary counts, needs-your-review, merge conflict indicator) are consistently implemented across the source skill (skills/status.md) and all four adapter copies (.claude/, .agents/, .cursor/, .gemini/).
• The {{STALE_DAYS}} template variable in the source is correctly resolved to the hardcoded 14 in all adapter files, matching the value in .codecannon.yaml.
• STALE_DAYS is properly added to config.schema.yaml with description, default, category, and used_in fields.
• Step references are updated correctly (skip Steps 2–5 changed to skip Steps 2–6 to account for the new step numbering).
• The --team flag is documented as mutually exclusive with --milestone/--sprint and username arguments, with explicit conflict handling.
• Team mode fetch commands include sensible limits (--limit 100 for PRs, --limit 200 for issues).
• The "What's next" priority table addition (row 3.5) is well-designed as an append-or-standalone behavior rather than a new exclusive row, avoiding disruption to existing priority logic.
• No secrets, .env files, or build artifacts committed.
• Documentation in docs/skills/status.md accurately reflects the skill changes.