add general file upload support with pool-aware tus client

- add "uploadFile" i18n key (en, zh-CN, zh-TW)
- introduce putFileToPool for tus upload with X-FilePool header
- add ComposeLogic.pickGeneralFile for arbitrary files
- extend uploadAttachment to support poolId override
- add toolbar button for general file upload

Signed-off-by: Texas0295 <kimura@texas0295.top>

lib/widgets/post/compose_shared.dart

@@ -1,4 +1,5 @@
 import 'package:collection/collection.dart';
+import 'package:mime/mime.dart';
 import 'package:dio/dio.dart';
 import 'package:easy_localization/easy_localization.dart';
 import 'package:file_picker/file_picker.dart';
@@ -386,6 +387,30 @@ class ComposeLogic {
     };
   }
 
+  static Future<void> pickGeneralFile(WidgetRef ref, ComposeState state) async {
+    final result = await FilePicker.platform.pickFiles(
+      type: FileType.any,
+      allowMultiple: true,
+    );
+    if (result == null || result.count == 0) return;
+
+    final newFiles = <UniversalFile>[];
+
+    for (final f in result.files) {
+      if (f.path == null) continue;
+
+      final mimeType =
+          lookupMimeType(f.path!, headerBytes: f.bytes) ??
+          'application/octet-stream';
+      final xfile = XFile(f.path!, name: f.name, mimeType: mimeType);
+
+      final uf = UniversalFile(data: xfile, type: UniversalFileType.file);
+      newFiles.add(uf);
+    }
+
+    state.attachments.value = [...state.attachments.value, ...newFiles];
+  }
+
   static Future<void> pickPhotoMedia(WidgetRef ref, ComposeState state) async {
     final result = await FilePicker.platform.pickFiles(
       type: FileType.image,
@@ -479,8 +504,9 @@ class ComposeLogic {
   static Future<void> uploadAttachment(
     WidgetRef ref,
     ComposeState state,
-    int index,
-  ) async {
+    int index, {
+    String? poolId,
+  }) async {
     final attachment = state.attachments.value[index];
     if (attachment.isOnCloud) return;
 
@@ -489,42 +515,61 @@ class ComposeLogic {
     if (token == null) throw ArgumentError('Token is null');
 
     try {
-      // Update progress state
       state.attachmentProgress.value = {
         ...state.attachmentProgress.value,
         index: 0,
       };
 
-      // Upload file to cloud
-      final cloudFile =
-          await putMediaToCloud(
-            fileData: attachment,
-            atk: token,
-            baseUrl: baseUrl,
-            filename: attachment.data.name ?? 'Post media',
-            mimetype:
-                attachment.data.mimeType ??
-                getMimeTypeFromFileType(attachment.type),
-            onProgress: (progress, _) {
-              state.attachmentProgress.value = {
-                ...state.attachmentProgress.value,
-                index: progress,
-              };
-            },
-          ).future;
+      SnCloudFile? cloudFile;
+
+      if (attachment.type == UniversalFileType.file) {
+        cloudFile =
+            await putFileToPool(
+              fileData: attachment,
+              atk: token,
+              baseUrl: baseUrl,
+              // TODO: Generic Pool ID (Now: Solian Network Driver)
+              poolId: poolId ?? '500e5ed8-bd44-4359-bc0a-ec85e2adf447',
+              filename: attachment.data.name ?? 'General file',
+              mimetype:
+                  attachment.data.mimeType ??
+                  getMimeTypeFromFileType(attachment.type),
+              onProgress: (progress, _) {
+                state.attachmentProgress.value = {
+                  ...state.attachmentProgress.value,
+                  index: progress,
+                };
+              },
+            ).future;
+      } else {
+        cloudFile =
+            await putMediaToCloud(
+              fileData: attachment,
+              atk: token,
+              baseUrl: baseUrl,
+              filename: attachment.data.name ?? 'Post media',
+              mimetype:
+                  attachment.data.mimeType ??
+                  getMimeTypeFromFileType(attachment.type),
+              onProgress: (progress, _) {
+                state.attachmentProgress.value = {
+                  ...state.attachmentProgress.value,
+                  index: progress,
+                };
+              },
+            ).future;
+      }
 
       if (cloudFile == null) {
         throw ArgumentError('Failed to upload the file...');
       }
 
-      // Update attachments list with cloud file
       final clone = List.of(state.attachments.value);
       clone[index] = UniversalFile(data: cloudFile, type: attachment.type);
       state.attachments.value = clone;
     } catch (err) {
-      showErrorAlert(err);
+      showErrorAlert(err.toString());
     } finally {
-      // Clean up progress state
       state.attachmentProgress.value = {...state.attachmentProgress.value}
         ..remove(index);
     }
@@ -643,7 +688,6 @@ class ComposeLogic {
             .where((entry) => entry.value.isOnDevice)
             .map((entry) => uploadAttachment(ref, state, entry.key)),
       );
-
       // Prepare API request
       final client = ref.watch(apiClientProvider);
       final isNewPost = originalPost == null;