docs: comprehensive OVSM documentation enhancement and production readiness

This commit represents a major documentation overhaul for the OVSM crate,
bringing it to production-ready, enterprise-grade documentation standards.

## Key Changes

### Phase 1: Core API Documentation Enhancement

1. **Error Documentation** (src/error.rs)
   - Enhanced all error types with three-tier documentation
   - Added trigger context, prevention tips, and recovery guidance
   - Examples for: UndefinedVariable, TypeError, DivisionByZero, etc.

2. **Parser Documentation** (src/parser/mod.rs)
   - Comprehensive module-level architecture documentation
   - Recursive descent parsing strategy explained
   - Operator precedence levels documented
   - Complete usage examples with Scanner → Parser → AST flow

3. **Runtime Evaluator Documentation** (src/runtime/evaluator.rs)
   - Tree-walking interpreter architecture explained
   - Environment and tool registry management documented
   - Control flow handling details with examples

4. **Tool Documentation** (src/tools/stdlib/*.rs)
   - Usage patterns and examples for all stdlib tools
   - Math: ABS(), SQRT(), POW() with syntax
   - Statistics: MIN(), MAX() with array examples
   - Utilities: LOG(), ERROR() with behavior notes

5. **AST Documentation** (src/parser/ast.rs)
   - Fixed rustdoc warning (escaped brackets)
   - All 300+ items properly documented

### Phase 2: User-Facing Documentation

6. **Common Patterns Guide** (docs/COMMON_PATTERNS.md) - NEW
   - 430 lines of comprehensive pattern library
   - 7 major sections: error handling, collections, loops, conditionals,
     validation, performance, testing
   - 3 real-world examples: data pipeline, search/filter, validation
   - Pattern selection guide with use case recommendations

7. **Troubleshooting Section** (USAGE_GUIDE.md)
   - Expanded from 3 to 10+ detailed error scenarios
   - Common runtime errors with solutions
   - Common parse errors with fixes
   - Block termination issues with 3 solutions
   - Performance debugging tips
   - Quick troubleshooting checklist

8. **README Enhancement** (README.md)
   - Added "Documentation Quality" section
   - Highlighted three-tier documentation approach
   - Enhanced error message features

### Phase 3: docs.rs Preparation

9. **Crate-Level Documentation** (src/lib.rs)
   - Comprehensive docs.rs landing page (265 lines)
   - Badges, features, quick start, installation
   - 3 complete usage examples with different complexity levels
   - Language overview, architecture diagram
   - Error handling examples, resource links
   - Ready for crates.io/docs.rs publication

10. **Documentation Generation**
    - Zero rustdoc warnings
    - Zero clippy warnings with -D warnings flag
    - All code examples compile correctly
    - 100% public API documented

## Documentation Metrics

- **300+ documented items** across OVSM crate
- **18 enhanced code examples** in lib.rs
- **30+ pattern examples** in COMMON_PATTERNS.md
- **50+ troubleshooting examples** in USAGE_GUIDE.md
- **1,000+ lines of documentation added**

## Quality Improvements

✅ Three-tier documentation (structure → purpose → usage)
✅ Enhanced errors with trigger/example/prevention/recovery
✅ Comprehensive pattern library for idiomatic code
✅ Detailed troubleshooting guide with checklists
✅ Production-ready docs.rs page with badges and examples
✅ Zero warnings or errors in documentation build

## Files Changed

Created:
- crates/ovsm/docs/COMMON_PATTERNS.md (430 lines)

Enhanced:
- crates/ovsm/src/lib.rs (13 → 267 lines)
- crates/ovsm/src/error.rs (+50 lines of context)
- crates/ovsm/src/parser/mod.rs (+60 lines)
- crates/ovsm/src/runtime/evaluator.rs (+80 lines)
- crates/ovsm/src/tools/stdlib/*.rs (+37 lines combined)
- crates/ovsm/USAGE_GUIDE.md (+400 lines in troubleshooting)
- crates/ovsm/README.md (+13 lines)

The OVSM crate now exemplifies documentation best practices with:
- Progressive disclosure from crate → module → function level
- Learning pathways from quick start → patterns → troubleshooting
- Context-rich errors that explain why, how to fix, and how to prevent

This positions OVSM as enterprise-ready and accessible to all skill levels.

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

Co-Authored-By: Claude <[email protected]>

Author: 0xrinegade

crates/ovsm/README.md

@@ -23,7 +23,9 @@ A production-ready interpreter for the OVSM scripting language, designed for blo
 - Comprehensive error messages
 
 📚 **Well Documented**
-- Complete API documentation
+- Complete API documentation with usage examples
+- Enhanced error messages with context and prevention tips
+- Three-tier documentation: structure, purpose, and usage
 - Usage guides and tutorials
 - Example scripts included
 - Interactive REPL for experimentation
@@ -172,11 +174,24 @@ cargo run --example simple_repl
 
 ## Documentation
 
-- [API Documentation](https://docs.rs/ovsm) - Complete API reference
+- [API Documentation](https://docs.rs/ovsm) - Complete API reference with usage examples
 - [Usage Guide](https://github.com/opensvm/osvm-cli/blob/main/crates/ovsm/USAGE_GUIDE.md) - Language syntax and features
 - [How to Use](https://github.com/opensvm/osvm-cli/blob/main/crates/ovsm/HOW_TO_USE.md) - Getting started guide
 - [Examples](https://github.com/opensvm/osvm-cli/tree/main/crates/ovsm/examples) - Sample scripts
 
+### Documentation Quality
+
+All public APIs are thoroughly documented with:
+- **Structure**: What the API is and its components
+- **Purpose**: What it does and when to use it
+- **Usage**: How to use it with practical examples
+
+Error messages include:
+- **Trigger context**: What causes the error
+- **Examples**: Concrete code that triggers it
+- **Prevention**: How to avoid the error
+- **Recovery**: Whether the error is recoverable
+
 ## Test Coverage
 
 - **Runtime Tests**: 65/65 passing ✅