feat: render native chat markdown via Textual

apps/shared/ClawdbotKit/Package.swift

@@ -5,7 +5,7 @@ import PackageDescription
 let package = Package(
     name: "ClawdbotKit",
     platforms: [
-        .iOS(.v17),
+        .iOS(.v18),
         .macOS(.v15),
     ],
     products: [
@@ -14,6 +14,7 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "https://github.com/steipete/ElevenLabsKit", exact: "0.1.0"),
+        .package(url: "https://github.com/gonzalezreal/textual", exact: "0.2.0"),
     ],
     targets: [
         .target(
@@ -29,7 +30,13 @@ let package = Package(
             ]),
         .target(
             name: "ClawdbotChatUI",
-            dependencies: ["ClawdbotKit"],
+            dependencies: [
+                "ClawdbotKit",
+                .product(
+                    name: "Textual",
+                    package: "textual",
+                    condition: .when(platforms: [.macOS, .iOS])),
+            ],
             swiftSettings: [
                 .enableUpcomingFeature("StrictConcurrency"),
             ]),