Add usage examples for JVM in README.md, including setup and composable integration

Author: kdroidFilter

README.md

@@ -8,6 +8,62 @@ Kotlin/JVM WebView using `wry` (Rust) with Gobley/UniFFI bindings, plus a Compos
 - `wrywebview-compose` - Compose `WryWebView` composable.
 - `demo` - sample Compose app.
 
+## Usage (JVM)
+
+1) Add the Compose wrapper module:
+
+```kotlin
+dependencies {
+    implementation(project(":wrywebview-compose"))
+}
+```
+
+2) Enable native access for the JVM process (required by JNA):
+
+```kotlin
+compose.desktop {
+    application {
+        jvmArgs += "--enable-native-access=ALL-UNNAMED"
+    }
+}
+```
+
+3) Use the composable:
+
+```kotlin
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import io.github.kdroidfilter.composewebview.WryWebView
+
+@Composable
+fun App() {
+    WryWebView(
+        url = "https://example.com",
+        modifier = Modifier.fillMaxSize(),
+    )
+}
+```
+
+Stateful usage (navigation, loading, current URL):
+
+```kotlin
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import io.github.kdroidfilter.composewebview.WryWebView
+import io.github.kdroidfilter.composewebview.rememberWebViewState
+
+@Composable
+fun App() {
+    val state = rememberWebViewState("https://example.com")
+
+    // Use state.canGoBack, state.canGoForward, state.isLoading, state.currentUrl
+    // and trigger state.goBack(), state.goForward(), state.reload(), state.loadUrl(...)
+    WryWebView(state = state, modifier = Modifier.fillMaxSize())
+}
+```
+
 ## Run the demo
 
 ```shell