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/proposal.md

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+# Change: Add Blog Post - 4 Essential Slash Commands for Development Workflow
+
+## Why
+
+The claude-howto project provides excellent reference documentation but lacks blog-style content that showcases real-world usage patterns. Users have found 4 slash commands particularly valuable across their development workflow, and a blog post explaining when/where/how to use each would help others adopt these productivity tools.
+
+## What Changes
+
+- Create new `blog-post/` directory for blog content
+- Add blog post: "4 Essential Slash Commands I Use in Every Project"
+- Cover 4 commands with practical guidance:
+  - `/push-all` - Quick deployment of coherent changes
+  - `/setup-ci-cd` - Post-POC quality infrastructure
+  - `/doc-refactor` - Post-MVP documentation polish
+  - `/unit-test-expand` - Milestone-driven test expansion
+- Reference the first slash commands blog: [Discovering Claude Code Slash Commands](https://medium.com/@luongnv89/discovering-claude-code-slash-commands-cdc17f0dfb29)
+- Link to full command files when content exceeds 30 lines
+
+## Impact
+
+- Affected specs: None (new capability)
+- Affected code: New `blog-post/` directory and content
+- No breaking changes

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

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+## ADDED Requirements
+
+### Requirement: Blog Post Directory Structure
+
+The project SHALL provide a `blog-post/` directory for hosting blog-style content that complements the reference documentation.
+
+#### Scenario: Blog post directory exists
+- **WHEN** a user navigates to the project root
+- **THEN** a `blog-post/` directory is present containing blog content
+
+### Requirement: Slash Commands Usage Blog Post
+
+The blog SHALL document 4 essential slash commands with practical usage guidance covering when, where, and how to use each command in a development workflow.
+
+#### Scenario: Complete command coverage
+- **WHEN** a user reads the blog post
+- **THEN** they find documentation for `/push-all`, `/setup-ci-cd`, `/doc-refactor`, and `/unit-test-expand`
+
+#### Scenario: Command file linking for long content
+- **WHEN** a command file exceeds 30 lines
+- **THEN** the blog SHALL provide a link to the full command file in the claude-howto project
+
+#### Scenario: Inline content for short commands
+- **WHEN** a command file is 30 lines or fewer
+- **THEN** the blog MAY include the command content inline
+
+### Requirement: Development Workflow Context
+
+Each command section SHALL explain when to use the command in the development lifecycle (POC, MVP, milestone phases).
+
+#### Scenario: Workflow phase guidance
+- **WHEN** a user reads a command section
+- **THEN** they understand which development phase the command is most appropriate for
+
+### Requirement: Reference to First Blog
+
+The blog post SHALL reference the introductory slash commands blog: "Discovering Claude Code Slash Commands" for foundational context.
+
+#### Scenario: Blog reference present
+- **WHEN** a user reads the introduction
+- **THEN** they find a link to the original slash commands blog post on Medium

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

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+## 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