fix: Suppress non-PMG error from Critical UI Error (#311)

* fix: Suppress non-PMG error from Critical UI Error

* fix: Code review fixes

---------

Co-authored-by: Sahil Bansal <bansalsahil315@gmail.com>

internal/proc/signal_unix_test.go

@@ -0,0 +1,58 @@
+//go:build !windows
+
+package proc
+
+import (
+	"syscall"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSignalInfo(t *testing.T) {
+	tests := []struct {
+		name         string
+		sys          any
+		wantSignum   int
+		wantSignaled bool
+	}{
+		{
+			name:         "SIGINT terminated process",
+			sys:          syscall.WaitStatus(int(syscall.SIGINT)),
+			wantSignum:   int(syscall.SIGINT),
+			wantSignaled: true,
+		},
+		{
+			name:         "SIGTERM terminated process",
+			sys:          syscall.WaitStatus(int(syscall.SIGTERM)),
+			wantSignum:   int(syscall.SIGTERM),
+			wantSignaled: true,
+		},
+		{
+			name:         "normal exit code 2 is not signaled",
+			sys:          syscall.WaitStatus(2 << 8),
+			wantSignum:   0,
+			wantSignaled: false,
+		},
+		{
+			name:         "nil status is not signaled",
+			sys:          nil,
+			wantSignum:   0,
+			wantSignaled: false,
+		},
+		{
+			name:         "non-WaitStatus value is not signaled",
+			sys:          "not a wait status",
+			wantSignum:   0,
+			wantSignaled: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			signum, signaled := SignalInfo(tt.sys)
+			assert.Equal(t, tt.wantSignaled, signaled)
+			assert.Equal(t, tt.wantSignum, signum)
+		})
+	}
+}