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/todo-structure.md

@@ -0,0 +1,94 @@
+# Task Structure: [Project Name]
+
+## Overview
+
+| Metric | Value |
+|--------|-------|
+| **Total Tasks** | [X] |
+| **Phases** | [Y] |
+| **Timeline** | [Start] → [End] |
+
+---
+
+## Phase 1: [Phase Name]
+
+**Target**: [Date]  
+**Owner**: [Name]
+
+| # | Task | Owner | Estimate | Due | Depends On | Status |
+|---|------|-------|----------|-----|------------|--------|
+| 1.1 | [Task description] | [Name] | [Xh/Xd] | [Date] | - | [ ] |
+| 1.2 | [Task description] | [Name] | [Xh/Xd] | [Date] | 1.1 | [ ] |
+| 1.3 | [Task description] | [Name] | [Xh/Xd] | [Date] | - | [ ] |
+
+**Phase Deliverable**: [What's complete when this phase is done]
+
+---
+
+## Phase 2: [Phase Name]
+
+**Target**: [Date]  
+**Owner**: [Name]
+
+| # | Task | Owner | Estimate | Due | Depends On | Status |
+|---|------|-------|----------|-----|------------|--------|
+| 2.1 | [Task description] | [Name] | [Xh/Xd] | [Date] | Phase 1 | [ ] |
+| 2.2 | [Task description] | [Name] | [Xh/Xd] | [Date] | 2.1 | [ ] |
+| 2.3 | [Task description] | [Name] | [Xh/Xd] | [Date] | - | [ ] |
+
+**Phase Deliverable**: [What's complete when this phase is done]
+
+---
+
+## Phase 3: [Phase Name]
+
+**Target**: [Date]  
+**Owner**: [Name]
+
+| # | Task | Owner | Estimate | Due | Depends On | Status |
+|---|------|-------|----------|-----|------------|--------|
+| 3.1 | [Task description] | [Name] | [Xh/Xd] | [Date] | Phase 2 | [ ] |
+| 3.2 | [Task description] | [Name] | [Xh/Xd] | [Date] | 3.1 | [ ] |
+| 3.3 | [Task description] | [Name] | [Xh/Xd] | [Date] | 3.1 | [ ] |
+
+**Phase Deliverable**: [What's complete when this phase is done]
+
+---
+
+## Unphased / Ongoing Tasks
+
+| # | Task | Owner | Frequency | Notes |
+|---|------|-------|-----------|-------|
+| O.1 | [Recurring task] | [Name] | Weekly | [Notes] |
+| O.2 | [Monitoring task] | [Name] | Daily | [Notes] |
+
+---
+
+## Dependencies Summary
+
+```
+Phase 1 ──────► Phase 2 ──────► Phase 3
+    │               │
+    ├── 1.1 ► 1.2   ├── 2.1 ► 2.2
+    └── 1.3         └── 2.3 (parallel)
+```
+
+## Milestone Checklist
+
+- [ ] **Milestone 1**: [Name] - [Date]
+  - [ ] [Required task 1.1]
+  - [ ] [Required task 1.2]
+
+- [ ] **Milestone 2**: [Name] - [Date]
+  - [ ] [Required task 2.1]
+  - [ ] [Required task 2.2]
+
+- [ ] **Project Complete** - [Date]
+  - [ ] All phases complete
+  - [ ] Success criteria met
+  - [ ] Handoff complete
+
+---
+
+*Created: [Date]*  
+*Last updated: [Date]*