feat: restore all 30 slash commands with comprehensive documentation

Restored 26 additional commands from commit d4a17fc, bringing total from 5 to 30 commands.

## New Commands Added (26):
- /analyze - Code and architecture analysis
- /brainstorm - Structured brainstorming sessions
- /build - Build and compilation workflows
- /business-panel - Multi-expert business analysis
- /cleanup - Code cleanup and refactoring
- /design - System design and architecture
- /document - Documentation generation
- /estimate - Effort and time estimation
- /explain - Code explanation
- /git - Git operations and workflows
- /help - Command help and usage
- /implement - Implementation workflows
- /improve - Code improvement suggestions
- /index - Project indexing (alias for index-repo)
- /load - Load saved sessions
- /pm - Project management workflows
- /reflect - Reflection and retrospectives
- /save - Save current session
- /select-tool - Tool selection guidance
- /spawn - Spawn parallel tasks
- /spec-panel - Multi-expert specification analysis
- /task - Task management
- /test - Testing workflows
- /troubleshoot - Debugging and troubleshooting
- /workflow - Custom workflow automation

## Documentation Updates:
- Created docs/reference/commands-list.md with categorized command reference
- Updated README.md with expandable 30-command list
- Updated README-zh.md with Chinese translations
- Updated README-ja.md with Japanese translations
- Updated README-kr.md with Korean translations
- Changed statistics: "3 plugins" → "30 commands"
- Added command categories: Planning & Design, Development, Testing & Quality,
  Documentation, Version Control, Project Management, Research & Analysis, Utilities

## Files Changed:
- 60 files changed, 7930 insertions(+), 267 deletions(-)
- Added 26 commands to plugins/superclaude/commands/
- Added 26 commands to src/superclaude/commands/
- Created comprehensive command documentation

Commands restored from: d4a17fc (superclaude/commands/)
Total: 30 commands now available

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

plugins/superclaude/commands/improve.md

@@ -0,0 +1,94 @@
+---
+name: improve
+description: "Apply systematic improvements to code quality, performance, and maintainability"
+category: workflow
+complexity: standard
+mcp-servers: [sequential, context7]
+personas: [architect, performance, quality, security]
+---
+
+# /sc:improve - Code Improvement
+
+## Triggers
+- Code quality enhancement and refactoring requests
+- Performance optimization and bottleneck resolution needs
+- Maintainability improvements and technical debt reduction
+- Best practices application and coding standards enforcement
+
+## Usage
+```
+/sc:improve [target] [--type quality|performance|maintainability|style] [--safe] [--interactive]
+```
+
+## Behavioral Flow
+1. **Analyze**: Examine codebase for improvement opportunities and quality issues
+2. **Plan**: Choose improvement approach and activate relevant personas for expertise
+3. **Execute**: Apply systematic improvements with domain-specific best practices
+4. **Validate**: Ensure improvements preserve functionality and meet quality standards
+5. **Document**: Generate improvement summary and recommendations for future work
+
+Key behaviors:
+- Multi-persona coordination (architect, performance, quality, security) based on improvement type
+- Framework-specific optimization via Context7 integration for best practices
+- Systematic analysis via Sequential MCP for complex multi-component improvements
+- Safe refactoring with comprehensive validation and rollback capabilities
+
+## MCP Integration
+- **Sequential MCP**: Auto-activated for complex multi-step improvement analysis and planning
+- **Context7 MCP**: Framework-specific best practices and optimization patterns
+- **Persona Coordination**: Architect (structure), Performance (speed), Quality (maintainability), Security (safety)
+
+## Tool Coordination
+- **Read/Grep/Glob**: Code analysis and improvement opportunity identification
+- **Edit/MultiEdit**: Safe code modification and systematic refactoring
+- **TodoWrite**: Progress tracking for complex multi-file improvement operations
+- **Task**: Delegation for large-scale improvement workflows requiring systematic coordination
+
+## Key Patterns
+- **Quality Improvement**: Code analysis → technical debt identification → refactoring application
+- **Performance Optimization**: Profiling analysis → bottleneck identification → optimization implementation
+- **Maintainability Enhancement**: Structure analysis → complexity reduction → documentation improvement
+- **Security Hardening**: Vulnerability analysis → security pattern application → validation verification
+
+## Examples
+
+### Code Quality Enhancement
+```
+/sc:improve src/ --type quality --safe
+# Systematic quality analysis with safe refactoring application
+# Improves code structure, reduces technical debt, enhances readability
+```
+
+### Performance Optimization
+```
+/sc:improve api-endpoints --type performance --interactive
+# Performance persona analyzes bottlenecks and optimization opportunities
+# Interactive guidance for complex performance improvement decisions
+```
+
+### Maintainability Improvements
+```
+/sc:improve legacy-modules --type maintainability --preview
+# Architect persona analyzes structure and suggests maintainability improvements
+# Preview mode shows changes before application for review
+```
+
+### Security Hardening
+```
+/sc:improve auth-service --type security --validate
+# Security persona identifies vulnerabilities and applies security patterns
+# Comprehensive validation ensures security improvements are effective
+```
+
+## Boundaries
+
+**Will:**
+- Apply systematic improvements with domain-specific expertise and validation
+- Provide comprehensive analysis with multi-persona coordination and best practices
+- Execute safe refactoring with rollback capabilities and quality preservation
+
+**Will Not:**
+- Apply risky improvements without proper analysis and user confirmation
+- Make architectural changes without understanding full system impact
+- Override established coding standards or project-specific conventions
+