Run environment none and stdio MCP in the agent-host views

[SaladDay]

Agent-host views now run Sessions with environment none and stdio MCP servers for Codex, Claude and MiniMax Code. Each view declares EnvironmentNone and StdioMCP Supported.

• Environment none. The view starts the Harness in /.oac/home/work without a workspace. It reuses the adapter's existing none settings, and Claude drops the environment variables that only the workspace tools need.

• Stdio MCP. Each adapter's existing stdio rendering now takes the command source as a parameter. A view passes the binding's alias with no arguments, and the process broker runs the frozen command in the sandbox. The view-only MCP renderers and the stdio rejections are deleted. The Claude bridge accepts a stdio server without args.

• Codex trust. The adapter writes no trust entry; Codex keeps its native project trust.

• Qualification. agenthostqualify adds two Turns for each kind that declares support:

  • an environment-none Turn, which must answer through the model and leave native state naming /.oac/home/work;
  • a stdio-MCP Turn, which must call a Python MCP server running in the sandbox.

  Real-Harness qualification passed for all three kinds.

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