feat: add Kode-Agent provider support

[CrazyBoyM]

Summary

Add Kode as a first-class provider in OpenShell. Kode is an open-source, multi-model AI coding agent that supports both Anthropic and OpenAI APIs through a unified terminal interface.

Changes

Provider plugin (crates/openshell-providers/)

• New kode.rs provider with ANTHROPIC_API_KEY and OPENAI_API_KEY credential discovery
• Registered in the provider registry and normalize_provider_type

CLI (crates/openshell-cli/)

• Added Kode variant to CliProviderType enum

Network policy (crates/openshell-sandbox/testdata/)

• Added kode_agent policy allowing api.anthropic.com and api.openai.com (port 443)
• Binary paths: /usr/local/bin/kode and /usr/bin/node

Documentation (docs/)

• Added Kode to supported agents table
• Added Kode to default policy compatibility matrix

Usage

# Auto-detected provider from command
openshell sandbox create -- kode

# Explicit provider
openshell provider create --name kode --type kode --from-existing

About Kode

• Package: @shareai-lab/kode (Apache 2.0)
• Command: kode
• Multi-model: Supports Anthropic (Claude) and OpenAI models simultaneously
• CLI compatible: Shares a similar CLI interface with Claude Code (--print, --model, --system-prompt, --permission-mode, etc.)
• Repository: https://github.com/shareAI-lab/Kode-Agent

Test plan

• Unit tests pass for kode.rs credential discovery (ANTHROPIC_API_KEY and OPENAI_API_KEY)
• normalize_provider_type("kode") returns Some("kode")
• detect_provider_from_command(&["kode"]) returns Some("kode")
• openshell sandbox create -- kode auto-detects the kode provider type
• Network policy allows kode binary to reach api.anthropic.com and api.openai.com

[github-actions]

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