fix(cdp): fast-fail cdp_status when the Dev Client picker blocks the bundle (closes #184)

[Lykhoyda]

Closes #184.

Problem

cdp_status({platform:'ios'}) with the Expo Dev Client "Development servers" picker up and Metro running hung ~33.5s, logged React not ready after 30000ms, then returned a misleading ok:true. Root cause: stale C++ targets pass filterValidTargets, the 1+1 pre-flight probe passes (the C++ connection answers), and performSetup's waitForReact(REACT_READY_TIMEOUT_MS=30_000) then burns its full 30s because the picker blocks the bundle so React never readies.

Fix

Thread a connect intent ('default' | 'status') through autoConnect → discoverAndConnect → connectToTarget. For a status-scoped connect against a non-Hermes target, run a bounded React-reachability probe (default 5s, RN_PICKER_PROBE_BUDGET_MS-overridable) before setup()'s 30s waitForReact. If React isn't reachable within the budget, throw the typed PickerBlockingBundleError — which bypasses both the connectToTarget retry loop and the discoverAndConnect candidate loop — and status.ts maps it to a fast failResult with code PICKER_BLOCKING and an actionable message:

Dev Client picker appears to be blocking the bundle … select your Metro server, then retry cdp_status.

A working Bridgeless app's target is also a [C++ connection], but its React is reachable, so the probe succeeds and the connect proceeds normally — only a genuinely blocked/never-ready target throws.

What it deliberately does NOT do (the two regressions #184 called out)

• Doesn't shorten the global REACT_READY_TIMEOUT_MS — it's shared by every connect path and would regress legitimate slow first-builds.
• Doesn't add a pre-autoConnect target-shape heuristic — /json/list returns 0 Hermes targets transiently during healthy reloads, so that would false-positive.
• Hermes targets skip the probe entirely (a slow Hermes first-build keeps the full budget); non-status connect paths (cdp_connect, feature-dev, reconnect) are completely unchanged.

Files (~5, as the issue estimated)

cdp/connect.ts (intent threading, PickerBlockingBundleError, shouldRunPickerProbe, probe + both catch sites), cdp/setup.ts (probeReactReachable), cdp-client.ts (intent param), tools/status.ts ('status' intent + mapping), types.ts (PICKER_BLOCKING code).

Testing

• 5 new unit tests for the extracted pure helpers (probeReactReachable, shouldRunPickerProbe, PickerBlockingBundleError), written failing-first — the connect layer opens a real WebSocket, so the decision logic is extracted into pure helpers per the repo's existing formatConnectFailureMessage/stickyPlatformFilters convention.
• Full suite: 1563 pass; tsc --noEmit clean; existing connect tests unaffected.
• The end-to-end picker-up assertion (cdp_status returns < ~6s) belongs to the deferred Dev Client harness CI (DC-Task 9 / Multi-device routing + dev-client picker hangs (combined session feedback) #136), per the issue.

🤖 Generated with Claude Code