v1.0.27: knot-inspired icon, fix media-not-found on photo open

Icon: two thick tube-style arcs with 3D glossy highlights.
  Arc 1 (left side): coral #E8665A to orange #E8A040
  Arc 2 (right side): steel blue #4A7FD4 to deep purple #7B5EA7
  Arrowheads: orange and purple. Background: dark purple-black.
  Inspired by the braided knot color palette.

Fix "media not found" when opening photos:
  - Intent now sets ClipData alongside FLAG_GRANT_READ_URI_PERMISSION
    so the permission correctly propagates through the system chooser
    to whichever app the user picks.
  - openFile() and downloadToCache() both call MediaScannerConnection
    so newly synced/downloaded files appear in gallery MediaStore index
    before the viewer launches.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/src/main/kotlin/com/syncflow/ui/files/FilesScreen.kt

@@ -1,5 +1,6 @@
 package com.syncflow.ui.files
 
+import android.content.ClipData
 import android.content.Intent
 import android.net.Uri
 import android.webkit.MimeTypeMap
@@ -57,15 +58,18 @@ fun FilesScreen(
                         val uri = FileProvider.getUriForFile(
                             context, "${context.packageName}.fileprovider", action.file
                         )
+                        val mimeType = action.file.name.mimeType()
                         val intent = Intent(Intent.ACTION_VIEW).apply {
-                            setDataAndType(uri, action.file.name.mimeType())
-                            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_ACTIVITY_NEW_TASK)
+                            setDataAndType(uri, mimeType)
+                            // ClipData is required so FLAG_GRANT_READ_URI_PERMISSION
+                            // propagates to whichever app the system chooser picks.
+                            clipData = ClipData.newRawUri("", uri)
+                            addFlags(
+                                Intent.FLAG_GRANT_READ_URI_PERMISSION or
+                                Intent.FLAG_ACTIVITY_NEW_TASK
+                            )
                         }
-                        context.startActivity(
-                            Intent.createChooser(intent, "Open with").apply {
-                                addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
-                            }
-                        )
+                        context.startActivity(intent)
                     } catch (e: Exception) {
                         snackbarHostState.showSnackbar("Cannot open file: ${e.message}")
                     }
@@ -78,6 +82,7 @@ fun FilesScreen(
                         val intent = Intent(Intent.ACTION_SEND).apply {
                             type = action.file.name.mimeType()
                             putExtra(Intent.EXTRA_STREAM, uri)
+                            clipData = ClipData.newRawUri("", uri)
                             addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_ACTIVITY_NEW_TASK)
                         }
                         context.startActivity(