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/risk-register.md

@@ -0,0 +1,104 @@
+# Risk Register: [Project Name]
+
+## Risk Summary
+
+| ID | Risk | Probability | Impact | Risk Score | Status |
+|----|------|-------------|--------|------------|--------|
+| R1 | [Brief risk name] | H/M/L | H/M/L | [H/M/L] | Open |
+| R2 | [Brief risk name] | H/M/L | H/M/L | [H/M/L] | Open |
+| R3 | [Brief risk name] | H/M/L | H/M/L | [H/M/L] | Open |
+
+**Risk Score**: Probability × Impact (H×H=Critical, H×M or M×H=High, M×M=Medium, others=Low)
+
+---
+
+## Detailed Risk Analysis
+
+### R1: [Risk Name]
+
+| Aspect | Detail |
+|--------|--------|
+| **Description** | [What could go wrong?] |
+| **Probability** | High / Medium / Low |
+| **Impact** | High / Medium / Low |
+| **Category** | Technical / Resource / External / Schedule / Budget |
+| **Trigger** | [What would indicate this risk is materializing?] |
+
+**Mitigation Plan**:
+- [Action 1 to reduce probability or impact]
+- [Action 2]
+
+**Contingency Plan** (if risk occurs):
+- [Fallback action 1]
+- [Fallback action 2]
+
+**Owner**: [Name]  
+**Review Date**: [Date]
+
+---
+
+### R2: [Risk Name]
+
+| Aspect | Detail |
+|--------|--------|
+| **Description** | [What could go wrong?] |
+| **Probability** | High / Medium / Low |
+| **Impact** | High / Medium / Low |
+| **Category** | Technical / Resource / External / Schedule / Budget |
+| **Trigger** | [What would indicate this risk is materializing?] |
+
+**Mitigation Plan**:
+- [Action 1]
+- [Action 2]
+
+**Contingency Plan**:
+- [Fallback action]
+
+**Owner**: [Name]  
+**Review Date**: [Date]
+
+---
+
+### R3: [Risk Name]
+
+| Aspect | Detail |
+|--------|--------|
+| **Description** | [What could go wrong?] |
+| **Probability** | High / Medium / Low |
+| **Impact** | High / Medium / Low |
+| **Category** | Technical / Resource / External / Schedule / Budget |
+| **Trigger** | [What would indicate this risk is materializing?] |
+
+**Mitigation Plan**:
+- [Action 1]
+- [Action 2]
+
+**Contingency Plan**:
+- [Fallback action]
+
+**Owner**: [Name]  
+**Review Date**: [Date]
+
+---
+
+## Risk Categories
+
+| Category | Examples |
+|----------|----------|
+| **Technical** | Technology doesn't work, integration issues, performance |
+| **Resource** | Key person unavailable, skill gaps, overcommitment |
+| **External** | Vendor delays, regulatory changes, dependencies |
+| **Schedule** | Delays, unrealistic timeline, competing priorities |
+| **Budget** | Cost overruns, funding cuts, unexpected expenses |
+
+## Review Schedule
+
+- **Weekly**: Quick scan of high risks
+- **Bi-weekly**: Full risk register review
+- **At milestones**: Comprehensive reassessment
+
+---
+
+*Created: [Date]*  
+*Last reviewed: [Date]*  
+*Next review: [Date]*