Rename directories to plural form: skill/ → skills/, agent/ → agents/, command/ → commands/

- Rename skill/ to skills/ for consistency with naming conventions
- Rename agent/ to agents/ and command/ to commands/
- Update AGENTS.md with all directory references
- Update scripts/test-skill.sh paths
- Update prompts/athena.txt documentation

This aligns with best practices of using plural directory names and updates
all documentation to reflect the new structure.

skills/plan-writing/assets/templates/progress-update.md

@@ -0,0 +1,89 @@
+# Progress Update: [Project Name]
+
+**Period**: [Date] to [Date]  
+**Author**: [Name]  
+**Status**: 🟢 On Track / 🟡 At Risk / 🔴 Blocked
+
+---
+
+## Summary
+
+[2-3 sentence executive summary: Where are we, what's the headline?]
+
+**Overall Progress**: [X]% complete
+
+---
+
+## Completed This Period
+
+- [x] [Task/milestone completed] - [Impact or note]
+- [x] [Task completed]
+- [x] [Task completed]
+
+**Highlights**:
+- [Notable achievement or win]
+
+---
+
+## In Progress
+
+| Task | Owner | Progress | Expected Complete |
+|------|-------|----------|-------------------|
+| [Task 1] | [Name] | [X]% | [Date] |
+| [Task 2] | [Name] | [X]% | [Date] |
+| [Task 3] | [Name] | [X]% | [Date] |
+
+---
+
+## Blockers & Risks
+
+### Active Blockers
+
+| Blocker | Impact | Owner | Action Needed | ETA |
+|---------|--------|-------|---------------|-----|
+| [Blocker 1] | [High/Med/Low] | [Name] | [What's needed] | [Date] |
+
+### Emerging Risks
+
+| Risk | Probability | Mitigation |
+|------|-------------|------------|
+| [Risk 1] | [H/M/L] | [Action] |
+
+---
+
+## Next Period Plan
+
+**Focus**: [Main focus for next period]
+
+| Priority | Task | Owner | Target Date |
+|----------|------|-------|-------------|
+| 1 | [Highest priority task] | [Name] | [Date] |
+| 2 | [Second priority] | [Name] | [Date] |
+| 3 | [Third priority] | [Name] | [Date] |
+
+---
+
+## Metrics
+
+| Metric | Target | Current | Trend |
+|--------|--------|---------|-------|
+| [Metric 1] | [X] | [Y] | ↑/↓/→ |
+| [Metric 2] | [X] | [Y] | ↑/↓/→ |
+| Tasks Complete | [X] | [Y] | ↑ |
+
+---
+
+## Decisions Needed
+
+- [ ] [Decision 1]: [Options and recommendation] - Need by: [Date]
+- [ ] [Decision 2]: [Context] - Need by: [Date]
+
+---
+
+## Notes / Context
+
+[Any additional context, changes in scope, stakeholder feedback, etc.]
+
+---
+
+*Next update: [Date]*