Managed GenericAgent Runtime

This document was split into topic files on 2026-07-04 for context economy. Start at the routing index: docs/managed-ga-runtime/README.md.

Section map:

• Product Model, First-Run UX Contract → product-and-onboarding.md
• Browser Control Capability → browser-control.md
• Runtime Modes, Session History, CLI Runtime Contract → runtime-modes-and-sessions.md
• Model Configuration (incl. ChatGPT / Codex OAuth, managed channels) → model-configuration.md
• Prompt Composition → prompt-composition.md
• Code And State, Patch Discipline, Backup And Device Migration → code-state-and-patches.md
• Implementation Plan (M0–M9), Verification → implementation-milestones.md