docs: update quick-start

docs-source/src/en/guide/quick-start.md

@@ -443,6 +443,12 @@ android {
     // - Note: If you disable this option, please make sure that there are no other projects
     //   that also use or not only Gropify to generate code to avoid conflicts.
     isIsolationEnabled = true
+
+    // Whether to use manifest placeholders' generation.
+    // 
+    // Disabled by default, when enabled will synchronize the properties' key-values
+    // to the `manifestPlaceholders` in the `android` configuration method block.
+    manifestPlaceholders = false
 }
 ```
 
@@ -638,6 +644,7 @@ In Android projects, many repetitive and fixed properties usually need to be con
 
 ```properties
 project.namespace=com.highcapable.gropifydemo
+project.appName=Gropify Demo
 project.compileSdk=36
 project.targetSdk=36
 project.minSdk=26
@@ -661,6 +668,24 @@ android {
 }
 ```
 
+When you set `manifestPlaceholders = true`, Gropify will automatically synchronize these properties' key-values to `manifestPlaceholders` in the android configuration method block.
+
+You can then use these placeholders directly in `AndroidManifest.xml`.
+
+> The following example
+
+```xml
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <application
+        android:label="${project.appName}"
+        android:icon="@mipmap/ic_launcher">
+
+        ...
+    </application>
+</manifest>
+```
+
 You no longer need to use `buildConfigField` to add code to `BuildConfig`. With the property key-value code generated by `Gropify`, you can manage your project more flexibly.
 
 You can also use interpolation `${...}` in property key-values to reference each other's content, but recursive references are not allowed.