fix(onboarding): stop assuming Codex App host

[Duang777]

Problem

register-agent and configure-goal do not know the active host, but both commands reused the Codex App upgrade scanner. A Trae App goal therefore reported codex_app_heartbeat as missing and told the operator to configure Codex App.

Fix

Return a host-neutral selection_required gate from generic registry commands. Keep exact Codex App, Trae App, and other host activation in start-goal and agent-onboard, where the caller supplies the host type.

Validation

• Added a regression that failed against the old codex_app_heartbeat result and passes with the host-neutral gate.
• Ran 167 focused host activation, guided start, registration, and fine-grained mode tests.
• Ran real CLI checks for register-agent, configure-goal, and Trae App start-goal.
• Ran loopx check: 3898 files scanned, 0 errors, 0 warnings.
• Ran loopx canary premerge --from-git-diff: 5 selected canaries passed.

[Duang777]

@huangruiteng This branch is updated to the latest main. All checks, including merge-gate, pass on exact head 8e7eda6eb0f1d8e8bddab7c2ee603f127206f535. The PR is ready for maintainer review and merge.

[Duang777]

Synced current main into exact head 87a9d0d8184056502bd82dc8542ad471a6e6fc9d without conflicts. The focused fresh-identity regression suite passes 2/2; CI is rerunning on the updated head.

[Duang777]

Synced latest main@952c1c0ae into exact head 66284f2b28ab59eeef43f43cf7728dbbaa2b202d without conflicts. Fresh focused validation: fresh-identity regressions 2/2 and Ruff passed. The superseded head had already passed both Stage 2C e2e jobs. New exact-head CI is starting.

[huangruiteng]

动机

这个 PR 修正 generic onboarding command 的宿主误判。register-agent 与 configure-goal 并没有拿到可证明的 Codex App host identity，却复用了 Codex App upgrade scan，导致 Trae 等非 Codex host 也收到“已探测 Codex App activation”的结果。这个输出会把 availability/projection 错当成调用方已经选择的宿主，属于对 operator 有实质误导的默认行为。

改动思路

改动没有猜测另一个宿主，也没有把 generic command 变成 host detector；它把 host-specific activation 留在拥有 agent_type 的 onboarding owner 中，而 generic registry path 只返回 unresolved + selection_required。这是最小且诚实的 contract：先通过 agent type catalog 选择 exact host，再进入相应 onboarding；generic registration 本身不授予或激活任何 host authority。

具体改动

• 从 registry_admin.py 移除 Codex App-specific build_upgrade_plan / loop_activation_for_goal 依赖。
• 新增小型 unresolved_host_loop_activation() 投影，明确 schema、host_surface=unresolved、status=selection_required、activated=false 和下一步操作。
• register-agent 的 normal/dry-run/write-denied result 与 configure-goal result 统一使用 neutral projection。
• 重命名并扩展 registration regression，断言 generic command 不再声称 Codex App，且返回可执行的 exact-host selection recommendation。

关键代码讲解

关键设计点不是新增 detector，而是删除错误的 implicit default。host-specific v1 contract 仍由 agent_onboarding.py / host_loop_activation.py 在明确 agent_type 后生成；这里的 v0 summary 只是 generic command 的 readback，并且 activated=false。因此一个可用的 Codex App 安装、某个凭据或现有文件都不会在未经选择时触发宿主 activation。状态值是 exact literal，不依赖 substring denylist 或 prose heuristic，也没有建立第二份持久状态。

对主干的风险

可见行为会变化：generic register-agent / configure-goal 不再默认返回 Codex App activation，而返回 selection required。PR body、测试名和输出 recommendation 都显式披露了 old/new behavior；已经明确走 exact agent_type 的 host-specific onboarding 不变。该 PR 不改 schema persistence、permission、quota、scheduler 或 runtime execution。当前 head 相对最新主干仅落后两个不相交提交，未发现冲突。

验证结果：registration/host suites 114 passed；Pi/unconnected/parity suites 11 passed；changed Python files 的 Ruff 通过；补齐 TypeScript parser dependencies 后 semantic vocabulary smoke 通过；loopx canary premerge --from-git-diff 5/5 通过，无 skip/failure。configure-goal 没有在本 PR 新增一条独立的精确断言，但它复用同一 helper，现有 parity/canary 覆盖未显示回归；这属于低残余风险，不构成阻塞。

我的整体评价

这次修改把 authority 与 capability availability 的边界拉回正确 owner：unknown host 保持 unknown，只有 exact host selection 才进入对应 activation contract。实现规模很小、调用点清楚、默认变化被披露，未发现需要阻塞的 correctness、typed-state、default-off 或兼容问题。我赞成在保持当前 exact head 的前提下合入。

English verdict: APPROVE - head 66284f2; generic onboarding now reports unresolved host selection instead of inventing Codex App activation; 125 focused tests, Ruff, semantic vocabulary smoke, and all 5 selected premerge canaries passed.