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/update-slash-commands-readme/specs/slash-commands/spec.md

@@ -0,0 +1,66 @@
+## ADDED Requirements
+
+### Requirement: Push-All Command with Safety Checks
+
+The documentation SHALL describe the `/push-all` command with its comprehensive safety workflow including:
+1. Change analysis (git status, diff, log)
+2. Safety checks for secrets, API keys, large files, build artifacts
+3. API key validation distinguishing real keys from placeholders
+4. Confirmation prompt before proceeding
+5. Conventional commit message generation
+6. Error handling guidance
+
+#### Scenario: User learns push-all safety workflow
+- **WHEN** a user reads the push-all command documentation
+- **THEN** they understand the multi-step safety workflow
+- **AND** they know what types of files trigger warnings
+- **AND** they understand they must confirm before execution
+
+---
+
+### Requirement: Doc-Refactor Command Documentation
+
+The documentation SHALL describe the `/doc-refactor` command for restructuring project documentation including:
+1. Project type analysis (library, API, web app, CLI, microservices)
+2. Documentation centralization in `docs/` folder
+3. Root README streamlining
+4. Component-level documentation
+5. Guide creation based on project type
+
+#### Scenario: User uses doc-refactor command
+- **WHEN** a user reads the doc-refactor documentation
+- **THEN** they understand how to invoke the command
+- **AND** they know what documentation structure changes to expect
+- **AND** they understand the command adapts to project type
+
+---
+
+### Requirement: Setup-CI-CD Command Documentation
+
+The documentation SHALL describe the `/setup-ci-cd` command for implementing quality gates including:
+1. Project analysis for language and tooling detection
+2. Pre-commit hook configuration with language-specific tools
+3. GitHub Actions workflow creation
+4. Pipeline verification steps
+
+#### Scenario: User uses setup-ci-cd command
+- **WHEN** a user reads the setup-ci-cd documentation
+- **THEN** they understand the command creates pre-commit hooks
+- **AND** they know GitHub Actions workflows will be generated
+- **AND** they understand tools are selected based on project language
+
+---
+
+### Requirement: Unit-Test-Expand Command Documentation
+
+The documentation SHALL describe the `/unit-test-expand` command for increasing test coverage including:
+1. Coverage analysis to identify gaps
+2. Gap identification (branches, error paths, boundaries)
+3. Framework-specific test generation
+4. Coverage verification
+
+#### Scenario: User uses unit-test-expand command
+- **WHEN** a user reads the unit-test-expand documentation
+- **THEN** they understand the command analyzes existing coverage
+- **AND** they know it targets untested branches and edge cases
+- **AND** they understand it works with their project's testing framework