[wanglongan587]

Summary

frozen modelContext -> bundled adapter/native CLI pair
  environment-only temporary token + private execution HOME
  pin primary/alias models and query routing; disable fallback
  acknowledge exact application before the host sends a prompt

Requires the startup contract in desktop#703. Draft dependency: JSR currently publishes SDK 0.10.0. After 0.11.0 is published, update the formal SDK pin and lock file, rerun normal checks, then request final review. No unpublished JSR version is invented here.

Legacy starts stay unchanged. Active model discovery reads only the frozen binding. Provider/model replacement is refused; private diagnostics are suppressed while protocol error codes and Effect restart behavior are retained.

ADR: plugin-owned-model-adapters remains approved. Declaration publication stays opt-in and disabled by default; host rollout and final production acceptance are separate.

Refs ora-space/circus#336

Evidence

• Before: startup ignored platform model context and used native credential/model discovery.
  After: full source checks against the SDK preview, lint, and 30 tests pass; missing bundled executables fail without local/PATH fallback.
• Verified fixed ACP adapter 0.94.0 / Agent SDK 0.3.303 / CLI 2.1.303 with two independent synthetic bindings, shared repository cwd, hostile project routing, two turns and a completed local tool per binding. All inference requests used the expected model; no token appeared in ACP frames, stderr or private HOME files.
• The controlled CLI fixture is not production Cloud multi-user acceptance. Normal published-SDK checks remain blocked until the dependency is released.

Merge Danger

Door: two-way

Code is reversible. SDK/package publication is a separate owner action; no release or declaration switch is performed.

Blast Radius: claude-adapter

Do not merge until the published SDK pin/lock and CI are updated. The model path supplies tokens through the child environment; programmatic settings contain no token literal because the pinned SDK serializes them into CLI arguments.

Refs ora-space/circus#354