fix(mobile): handle iOS share sheet custom scheme URLs and add photo library picker

On iOS the Share Sheet / "Open In" action may deliver the file path
under the app's custom docuelevate:// scheme instead of a file:// URL,
causing an "Unmatched Route" error.  The URL handler now detects this
and rewrites the URL to file:// before processing.

Also adds a Photo Library button to the Upload screen so users can
select existing photos from their device library, not just capture
new ones with the camera.

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

mobile/README.md

@@ -6,6 +6,7 @@ Native mobile application for DocuElevate, built with **React Native** and **Exp
 
 - 🔐 **SSO Login** – authenticate via your DocuElevate server's OAuth2/SSO provider; an API token is auto-generated and stored securely in the device keychain
 - 📷 **Camera Capture** – scan documents directly with the device camera
+- 🖼️ **Photo Library** – select existing photos from the device's photo library for upload
 - 📄 **File Picker** – upload PDFs, images, and Office documents from the device's Files app
 - 🔗 **Share Extension** – send files from any app directly to DocuElevate via the iOS/Android share sheet
 - 🔔 **Push Notifications** – receive real-time push notifications when documents finish processing (via Expo push notifications)
@@ -145,7 +146,7 @@ mobile/
     ├── screens/
     │   ├── WelcomeScreen.tsx      # Branded intro / onboarding
     │   ├── LoginScreen.tsx        # SSO login
-    │   ├── UploadScreen.tsx       # Camera capture + file picker
+    │   ├── UploadScreen.tsx       # Camera capture + photo library + file picker
     │   ├── FilesScreen.tsx        # Document list
     │   └── ProfileScreen.tsx      # User profile + sign out
     └── services/
@@ -158,9 +159,9 @@ The app registers itself as a share target so any file can be sent directly to D
 
 ### iOS – how it works
 
-`app.json` declares `CFBundleDocumentTypes` in the iOS `infoPlist` section.  This tells iOS which file types the app can receive, causing it to appear in the share sheet when the user shares a matching file.  When the user taps **DocuElevate** in the share sheet, iOS passes the file path to the app via `application:openURL:options:`, which React Native forwards as a `file://` URL through the `Linking` module.
+`app.json` declares `CFBundleDocumentTypes` in the iOS `infoPlist` section.  This tells iOS which file types the app can receive, causing it to appear in the share sheet when the user shares a matching file.  When the user taps **DocuElevate** in the share sheet, iOS passes the file path to the app via `application:openURL:options:`.  The URL may arrive as a standard `file://` path or under the app's custom `docuelevate://` scheme.
 
-The root layout (`app/_layout.tsx`) listens for incoming `file://` URLs via `Linking.addEventListener` (warm start) and `Linking.getInitialURL()` (cold start).  Incoming files are stored in `ShareContext` and automatically uploaded by `UploadScreen`.
+The root layout (`app/_layout.tsx`) listens for incoming URLs via `Linking.addEventListener` (warm start) and `Linking.getInitialURL()` (cold start).  If the URL uses the `docuelevate://` scheme it is automatically rewritten to `file://` before being forwarded.  Incoming files are stored in `ShareContext` and automatically uploaded by `UploadScreen`.
 
 **Supported iOS file types:** PDF, images (JPEG / PNG / GIF / BMP / TIFF / WebP), plain text, Word (`.docx`, `.doc`), Excel (`.xlsx`, `.xls`), PowerPoint (`.pptx`, `.ppt`), and any other file (`public.data`).
 

mobile/app/_layout.tsx

@@ -39,11 +39,29 @@ function filenameFromUri(uri: string): string {
  * Build a Linking URL handler that forwards incoming file:// / content://
  * URLs to ShareContext.  Extracted as a module-level factory so the handler
  * itself is created once and can be easily unit-tested without a React context.
+ *
+ * On iOS the Share Sheet / "Open In" action may deliver the file path under
+ * the app's custom URL scheme (e.g.
+ * `docuelevate://private/var/mobile/Library/…/file.pdf`) instead of a plain
+ * `file://` URL.  When that happens we rewrite the URL to `file:///…` so the
+ * upload logic can read the file normally.
  */
 function makeUrlHandler(addPendingFile: (f: { uri: string; filename: string }) => void) {
   return ({ url }: { url: string }) => {
-    if (!url.startsWith("file://") && !url.startsWith("content://")) return;
-    addPendingFile({ uri: url, filename: filenameFromUri(url) });
+    let fileUri = url;
+
+    // iOS may pass a filesystem path under the app's custom scheme.
+    // Rewrite it to a file:// URL unless it looks like an in-app deep-link
+    // (expo-router groups always start with "(").
+    if (url.startsWith("docuelevate://")) {
+      const path = url.slice("docuelevate://".length);
+      if (path.length > 0 && !path.startsWith("(")) {
+        fileUri = "file:///" + path.replace(/^\/+/, "");
+      }
+    }
+
+    if (!fileUri.startsWith("file://") && !fileUri.startsWith("content://")) return;
+    addPendingFile({ uri: fileUri, filename: filenameFromUri(fileUri) });
   };
 }
 

mobile/src/screens/UploadScreen.tsx

@@ -1,10 +1,11 @@
 /**
- * UploadScreen – document upload via camera or file picker.
+ * UploadScreen – document upload via camera, photo library, or file picker.
  *
  * Users can:
  * 1. Take a photo of a document with the device camera.
- * 2. Pick an existing file (PDF, image, Office document) from the Files app.
- * 3. Receive files shared from other apps via the iOS Share Sheet / Android
+ * 2. Select an existing photo from the device's photo library.
+ * 3. Pick an existing file (PDF, image, Office document) from the Files app.
+ * 4. Receive files shared from other apps via the iOS Share Sheet / Android
  *    Share Intent (handled via ShareContext populated by the root layout).
  *
  * After a successful upload the screen polls the backend every 5 seconds to
@@ -161,6 +162,29 @@ export default function UploadScreen() {
     }
   }
 
+  async function handlePhotoLibrary() {
+    const { status } = await ImagePicker.requestMediaLibraryPermissionsAsync();
+    if (status !== "granted") {
+      Alert.alert(
+        "Photo library access required",
+        "Please grant photo library access in Settings to select images."
+      );
+      return;
+    }
+
+    const result = await ImagePicker.launchImageLibraryAsync({
+      mediaTypes: ["images"],
+      quality: 0.9,
+      allowsEditing: false,
+    });
+
+    if (!result.canceled && result.assets.length > 0) {
+      const asset = result.assets[0];
+      const filename = asset.fileName ?? `photo_${Date.now()}.jpg`;
+      await uploadFile(asset.uri, filename, asset.mimeType ?? "image/jpeg");
+    }
+  }
+
   async function handleFilePicker() {
     try {
       const result = await DocumentPicker.getDocumentAsync({
@@ -201,6 +225,16 @@ export default function UploadScreen() {
           <Text style={styles.actionLabel}>Camera</Text>
         </Pressable>
 
+        <Pressable
+          style={[styles.actionButton, styles.photoLibraryButton]}
+          onPress={handlePhotoLibrary}
+          accessibilityRole="button"
+          accessibilityLabel="Select photo from library"
+        >
+          <Text style={styles.actionIcon}>🖼️</Text>
+          <Text style={styles.actionLabel}>Photos</Text>
+        </Pressable>
+
         <Pressable
           style={[styles.actionButton, styles.fileButton]}
           onPress={handleFilePicker}
@@ -208,7 +242,7 @@ export default function UploadScreen() {
           accessibilityLabel="Pick file from device"
         >
           <Text style={styles.actionIcon}>📄</Text>
-          <Text style={styles.actionLabel}>File Picker</Text>
+          <Text style={styles.actionLabel}>Files</Text>
         </Pressable>
       </View>
 
@@ -218,7 +252,7 @@ export default function UploadScreen() {
           <View style={styles.emptyState}>
             <Text style={styles.emptyEmoji}>☁️</Text>
             <Text style={styles.emptyText}>
-              Tap Camera or File Picker to upload a document.
+              Tap Camera, Photos, or Files to upload a document.
             </Text>
             <Text style={styles.emptyHint}>
               You can also share files from other apps directly to DocuElevate.
@@ -304,6 +338,7 @@ const styles = StyleSheet.create({
     minHeight: 80,
   },
   cameraButton: { backgroundColor: "#1e40af" },
+  photoLibraryButton: { backgroundColor: "#7c3aed" },
   fileButton: { backgroundColor: "#059669" },
   actionIcon: { fontSize: 28, marginBottom: 6 },
   actionLabel: {