chore: initial commit of ai site platform

Co-authored-by: Cursor <cursoragent@cursor.com>

platform/internal/userstore/tenant_slug_test.go

@@ -0,0 +1,19 @@
+package userstore
+
+import "testing"
+
+func TestNormalizeTenantSlug(t *testing.T) {
+	ok, err := NormalizeTenantSlug("Aaa-01")
+	if err != nil || ok != "aaa-01" {
+		t.Fatalf("got %q %v", ok, err)
+	}
+	if _, err := NormalizeTenantSlug("api"); err == nil {
+		t.Fatal("api should be reserved")
+	}
+	if _, err := NormalizeTenantSlug("1abc"); err == nil {
+		t.Fatal("must start with letter")
+	}
+	if SuggestTenantSlug("Hello World") != "hello-world" {
+		t.Fatalf("suggest ascii")
+	}
+}