feat: release 2.2.0 with PC-only tests and execution reliability fixes

Unify task scheduling and queue state, fix Android input and observation recovery, preserve screenshot paths, and match final review criteria accurately. Add collapsible copyable results and publish the complete 2.1.0 upgrade notes. Validation: 3189 backend tests, 326 frontend tests, 24 client tests, production build and quality gates.

tests/unit/agents/test_execution_incident_prompt.py

@@ -145,6 +145,19 @@ def test_render_shifted_and_occupied_evidence():
     assert "now covered by 'Sign Up' button" in text
 
 
+def test_unavailable_pixel_verification_does_not_claim_target_disappeared():
+    incident = _disappeared(
+        category="pixel_verification_unavailable",
+        reason="Failed to acquire live screenshot: device offline",
+    )
+    text = render_execution_incident(incident, STEPS)
+    assert "device offline" in text
+    assert "was NOT executed" in text
+    assert "Restore a working observation" in text
+    assert "no longer on screen" not in text
+    assert "Your last dispatched action" not in text
+
+
 def test_render_burst_abort_and_exec_error():
     burst = _disappeared(kind=KIND_EXEC_ERROR, category="general", burst_size=3, action_index=1)
     burst["reason"] = "Error: tap rejected"