docs: Add blog post and new slash commands for development workflow

- Add blog post: 4 Essential Slash Commands I Use in Every Project
- Add new slash commands: /doc-refactor, /setup-ci-cd, /unit-test-expand
- Update slash-commands README with comprehensive documentation
- Simplify /push-all command structure
- Archive add-blog-post-slash-commands change
- Add blog-post spec and pending openspec changes

openspec/changes/archive/2025-12-26-add-blog-post-slash-commands/tasks.md

@@ -0,0 +1,25 @@
+## 1. Setup
+
+- [x] 1.1 Create `blog-post/` directory at project root
+
+## 2. Blog Post Creation
+
+- [x] 2.1 Create blog post markdown file with proper structure
+- [x] 2.2 Write introduction referencing first slash commands blog
+- [x] 2.3 Document `/push-all` with link to full command (152 lines)
+- [x] 2.4 Document `/setup-ci-cd` with inline content (25 lines)
+- [x] 2.5 Document `/doc-refactor` with inline content (23 lines)
+- [x] 2.6 Document `/unit-test-expand` with inline content (24 lines)
+- [x] 2.7 Add workflow diagram showing when to use each command
+- [x] 2.8 Write conclusion with development lifecycle integration
+
+## 3. Integration
+
+- [x] 3.1 Add blog-post to main README navigation
+- [x] 3.2 Cross-reference from slash-commands README
+
+## 4. Verification
+
+- [x] 4.1 Verify all internal links work
+- [x] 4.2 Verify external links are valid
+- [x] 4.3 Review content for clarity and accuracy