docs(learning-hub): update CLI session commands and personal skills path (#1165)

- Add /cd command documentation (per-session working directory, v1.0.11)
- Add --effort shorthand flag for --reasoning-effort (v1.0.10)
- Fix outdated personal skills directory path: ~/.copilot/skills/ -> ~/.agents/skills/ (v1.0.11)
- Update lastUpdated dates

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

website/src/content/docs/learning-hub/copilot-configuration-basics.md

@@ -3,7 +3,7 @@ title: 'Copilot Configuration Basics'
 description: 'Learn how to configure GitHub Copilot at user, workspace, and repository levels to optimize your AI-assisted development experience.'
 authors:
   - GitHub Copilot Learning Hub Team
-lastUpdated: 2026-03-24
+lastUpdated: 2026-03-25
 estimatedReadingTime: '10 minutes'
 tags:
   - configuration
@@ -413,6 +413,22 @@ The `/undo` command reverts the last turn—including any file changes the agent
 
 Use `/undo` when the agent's last response went in an unwanted direction and you want to try a different approach from that point.
 
+The `/cd` command changes the working directory for the current session. Each session maintains its own working directory that persists when you switch between sessions:
+
+```
+/cd ~/projects/my-other-repo
+```
+
+This is useful when you have multiple backgrounded sessions each focused on a different project directory.
+
+The `--effort` flag (shorthand for `--reasoning-effort`) controls how much computational reasoning the model applies to a request:
+
+```bash
+gh copilot --effort high "Refactor the authentication module"
+```
+
+Accepted values are `low`, `medium`, and `high`. You can also set a default via the `effortLevel` config setting.
+
 ## Common Questions
 
 **Q: How do I disable Copilot for specific files?**

website/src/content/docs/learning-hub/using-copilot-coding-agent.md

@@ -3,7 +3,7 @@ title: 'Using the Copilot Coding Agent'
 description: 'Learn how to use GitHub Copilot coding agent to autonomously work on issues, generate pull requests, and automate development tasks.'
 authors:
   - GitHub Copilot Learning Hub Team
-lastUpdated: 2026-02-26
+lastUpdated: 2026-03-25
 estimatedReadingTime: '12 minutes'
 tags:
   - coding-agent
@@ -267,7 +267,7 @@ Skills are stored in a `skills/` subdirectory, with each skill in its own folder
 
 **Personal skills** (shared across all your projects):
 ```
-~/.copilot/
+~/.agents/
 └── skills/
     └── code-review-checklist/
         └── SKILL.md