Summary

Document the HTTP/2 advanced features including HPACK header compression, server-side streaming, and the HTTP/2 library internals.

Parent Issue

Part of: [EPIC] docs: Address documentation gaps across all ecosystem systems (kcenon/common_system#325)

Background (Why)

network_system's HTTP/2 implementation at libs/network-http2/ includes advanced features beyond basic request/response that are undocumented:

• HPACK header compression (RFC 7541)
• Server-side streaming
• HTTP/2 frame handling internals

These are key differentiators vs HTTP/1.1 that users need documentation for.

Source files:

• libs/network-http2/include/network_http2/internal/hpack.h — HPACK header compression
• libs/network-http2/include/network_http2/http2_server_stream.h — Server-side streaming
• libs/network-http2/include/network_http2/http2_client.h — HTTP/2 client
• libs/network-http2/include/network_http2/http2_server.h — HTTP/2 server
• libs/network-http2/include/network_http2/http2_request.h — Request types
• libs/network-http2/include/network_http2/http2.h — Common HTTP/2 types

Scope (What)

1. HTTP/2 Architecture Overview

• Frame-based protocol internals
• Stream multiplexing model
• Flow control implementation
• HPACK compression integration

2. HPACK Header Compression (hpack.h)

• Static table (RFC 7541 Appendix A)
• Dynamic table management
• Encoding/decoding API
• Compression ratio characteristics
• Custom header optimization

3. Server-Side Streaming (http2_server_stream.h)

• Server push and streaming API
• Stream lifecycle management
• Flow control and backpressure
• Multiple concurrent streams

4. HTTP/2 Client (http2_client.h)

• Connection setup with ALPN negotiation
• Multiplexed request sending
• Response stream handling
• Connection pooling

5. HTTP/2 Server (http2_server.h)

• Server setup and configuration
• Request routing
• Stream handling
• Server push initiation

6. Performance Characteristics

• Header compression savings (typical 60-90% reduction)
• Multiplexing throughput vs HTTP/1.1 pipelining
• Stream concurrency limits and tuning

7. Usage Examples

• Basic HTTP/2 server with routing
• Client with multiplexed requests
• Server-sent events via streaming
• Bidirectional streaming

Acceptance Criteria

• HTTP/2 architecture documented
• HPACK compression API documented
• Server streaming API documented
• Client and server setup documented
• Performance comparison with HTTP/1.1
• At least 4 code examples