fix(store): handle global scope in normalizeScope (#428)

normalizeScope had no case for "global", silently coercing it to
"project". Add "global" alongside "personal" in the switch so
mem_save/mem_update/HTTP API callers can create and upsert global
observations correctly.

Closes #122

Author: Alan-TheGentleman

internal/store/store.go

@@ -5816,10 +5816,12 @@ func truncate(s string, max int) string {
 
 func normalizeScope(scope string) string {
 	v := strings.TrimSpace(strings.ToLower(scope))
-	if v == "personal" {
-		return "personal"
+	switch v {
+	case "personal", "global":
+		return v
+	default:
+		return "project"
 	}
-	return "project"
 }
 
 // NormalizeProject applies canonical project name normalization:

internal/store/store_test.go

@@ -7716,6 +7716,32 @@ func TestGetDeferred_NotFound(t *testing.T) {
 	}
 }
 
+func TestNormalizeScopeHandlesGlobal(t *testing.T) {
+	tests := []struct {
+		input string
+		want  string
+	}{
+		{"global", "global"},
+		{"Global", "global"},
+		{"GLOBAL", "global"},
+		{"  global  ", "global"},
+		{"personal", "personal"},
+		{"Personal", "personal"},
+		{"project", "project"},
+		{"Project", "project"},
+		{"", "project"},
+		{"unknown", "project"},
+	}
+	for _, tc := range tests {
+		t.Run(tc.input, func(t *testing.T) {
+			got := normalizeScope(tc.input)
+			if got != tc.want {
+				t.Errorf("normalizeScope(%q) = %q, want %q", tc.input, got, tc.want)
+			}
+		})
+	}
+}
+
 // TestSearchLegacyMixedCaseProject reproduces issue #146:
 // observations stored with a mixed-case project name (legacy data pre-normalization)
 // must be found when searched with a normalized (lowercase) project name.