Add Panama system health diagnostics

tests/quickshell/fixtures/doctor/bin/pgrep

@@ -0,0 +1,10 @@
+#!/usr/bin/bash
+
+set -euo pipefail
+
+name="${!#}"
+case ",${PANAMA_DOCTOR_FIXTURE_PROCESSES:-}," in
+    *",$name:duplicate,"*) printf '4101\n4102\n' ;;
+    *",$name:missing,"*) exit 1 ;;
+    *) printf '4101\n' ;;
+esac