docs(gfql): Comprehensive GFQL documentation with Let, Call, and advanced patterns

[lmeyerov]

Summary

This PR provides comprehensive GFQL documentation that stacks on top of the code implementation in PR #717. This documentation covers all the advanced features and patterns that were missing from the incomplete PRs #715/#716 extraction work.

Stacked PR Structure:

• Base PR feat(gfql): Complete GFQL implementation with AST, Let, and Call operations #717: Complete GFQL code implementation (AST, Let, Call, validation)
• This PR docs(gfql): Comprehensive GFQL documentation with Let, Call, and advanced patterns #718: Complete GFQL documentation stacked on the code PR

Documentation Scope

Complete GFQL Specification

• Language specification: Core grammar, operations, patterns
• Wire protocol: JSON serialization for cross-language compatibility
• Python embedding: Complete API reference with examples
• Cypher mapping: Translation guide from Cypher to GFQL

Advanced Features Documentation

• Let Bindings: DAG patterns with named, reusable graph operations
• Call Operations: Safe method execution with comprehensive safelist
• Remote Execution: GPU acceleration and distributed compute patterns
• Validation Framework: Error handling, schema validation, production patterns

Comprehensive Examples

• Basic patterns: Node/edge filtering, multi-hop traversals
• Complex DAG patterns: Multi-step investigations with Let bindings
• Call operation examples: PageRank, community detection, layouts
• Remote patterns: GPU execution, data upload optimization
• Production patterns: Error handling, security, API integration

Key Documentation Updates

Let Bindings for DAG Patterns

# Multi-step analysis with reusable components
investigation = g.gfql(let({
    'suspects': n({'risk_score': gt(8)}),
    'contacts': ref('suspects', [e(), n()]),
    'evidence': ref('contacts', [e_forward({'type': 'transaction'})])
}))

Call Operations Documentation

# Graph algorithms and transformations
result = g.gfql([
    call('compute_cugraph', {'alg': 'pagerank', 'out_col': 'influence'}),
    call('layout_cugraph', {'layout': 'force_atlas2'})
])

Remote Execution Patterns

# Complex remote analysis entirely in GFQL
analysis = g.gfql_remote(let({
    'ranked': call('compute_pagerank', {'columns': ['pagerank']}),
    'influencers': ref('ranked', [n({'pagerank': gt(0.02)})]),
    'network': ref('influencers', [e_forward(hops=2)])
}))

Files Updated

Total: 18 documentation files + 1 new demo notebook

Core Documentation (15 files)

• GFQL specification (language, wire protocol, python embedding)
• Tutorial and quick reference updates
• Validation framework documentation
• Remote execution and advanced patterns
• Translation guides (Cypher, SQL, Pandas)

New Demo Notebook (1 file)

• demos/gfql/call_operations.ipynb: 502 lines demonstrating Call operations

Updated Integration Documentation (3 files)

• Main tutorial integration with Let patterns
• Notebook index with Call operations
• Combined AI/ML workflows

Advanced Patterns Documented

Complex Investigation Patterns

• Multi-step graph traversals with Let bindings
• Reusable named patterns for investigations
• DAG dependency resolution and execution ordering

Remote GPU Acceleration

• Let patterns for remote-only execution
• GPU algorithm integration with Call operations
• Data upload optimization strategies

Production-Ready Patterns

• Error handling and validation strategies
• Security considerations for Call operations
• API integration with structured error codes

Addresses Documentation Gap

PRs #715/#716 missed ~80% of the advanced GFQL documentation. This PR provides:

• Complete Let binding documentation
• Full Call operations reference
• Advanced DAG patterns
• Remote execution strategies
• Production deployment guides
• Comprehensive examples and tutorials

Dependencies

• Requires PR feat(gfql): Complete GFQL implementation with AST, Let, and Call operations #717: This documentation PR stacks on the code implementation
• Backward compatible: All documentation updates are additive

Test Plan

• All documentation builds correctly
• Code examples match implementation in PR feat(gfql): Complete GFQL implementation with AST, Let, and Call operations #717
• Let binding examples demonstrate proper DAG patterns
• Call operation examples use valid safelist methods
• Remote execution examples show correct API usage
• Cross-references between docs work correctly

🤖 Generated with Claude Code

[lmeyerov]

Companion PR: This documentation PR works together with code PR #717.

Relationship:

• PR feat(gfql): Complete GFQL implementation with AST, Let, and Call operations #717: Complete GFQL code implementation (31 files + 16 test files)
• This PR (docs(gfql): Comprehensive GFQL documentation with Let, Call, and advanced patterns #718): Complete GFQL documentation (18 documentation files)
• Stacking: This PR is based on feat(gfql): Complete GFQL implementation with AST, Let, and Call operations #717 to ensure documentation examples work with the implementation

CI Status: ✅ All checks GREEN
Supersedes: PRs #708, #709, #716 (comprehensive extraction from PR #708)

Both PRs should be merged together to provide the complete GFQL feature set.

[lmeyerov]

Closing in favor of #719 which consolidates all documentation improvements into a clean stack: master ← #717 (code) ← #719 (docs)