Reorganize: Move all skills to skills/ folder

- Created skills/ directory
- Moved 272 skills to skills/ subfolder
- Kept agents/ at root level
- Kept installation scripts and docs at root level

Repository structure:
- skills/           - All 272 skills from skills.sh
- agents/           - Agent definitions
- *.sh, *.ps1       - Installation scripts
- README.md, etc.   - Documentation

Co-Authored-By: Claude <noreply@anthropic.com>

skills/plugins/cache/zai-coding-plugins/glm-plan-usage/0.0.1/commands/usage-query.md

@@ -0,0 +1,12 @@
+---
+allowed-tools: all
+description: Query the usage information for the current account
+---
+
+# Usage Query
+
+Invoke @glm-plan-usage:usage-query-agent to retrieve the usage information for the current account.
+
+## Critical constraint
+
+**Run the query exactly once** — regardless of success or failure, execute a single query and return the result immediately.