v0.2.3: fix export write failures and Ctrl+C cancellation

- Add ensure_directory calls in both export functions (preview + original)
- Include NSError.localizedDescription in write failed messages
- Make semaphore_wait_with_timeout poll photos_cancelled every ~1s
- Add status messages: auth, loading tree, per-album progress
- Fix parallel export: slot-based progress shows results in order

Makefile

@@ -1,6 +1,6 @@
 BINARY     := ./bin/photoscli
 MODULE     := gitea.k3s.k0.nu/tools/photocli
-VERSION    := 0.2.1
+VERSION    := 0.2.3
 BRIDGE_DIR := bridge
 LDFLAGS    := -X main.version=$(VERSION)
 OBJ        := $(BRIDGE_DIR)/photokit_bridge.o

bridge/photokit_bridge.m

@@ -274,6 +274,10 @@ char *photos_export_preview_json(const char *asset_id, const char *output_dir, i
     NSString *nsOutputDir = [NSString stringWithUTF8String:output_dir];
     if (!nsAssetId || !nsOutputDir) return json_from_object(make_error_dict(@"invalid UTF-8 in arguments"));
 
+    if (!ensure_directory(nsOutputDir)) {
+        return json_from_object(make_error_dict(@"failed to create output directory"));
+    }
+
     PHFetchResult<PHAsset *> *fetch = [PHAsset fetchAssetsWithLocalIdentifiers:@[nsAssetId] options:nil];
     if (fetch.count == 0) return json_from_object(make_error_dict(@"asset not found"));
 
@@ -322,7 +326,8 @@ char *photos_export_preview_json(const char *asset_id, const char *output_dir, i
 
     NSError *writeErr = nil;
     if (![imageData writeToFile:filepath options:NSDataWritingAtomic error:&writeErr]) {
-        return json_from_object(@{@"error": @"write failed", @"cloud": asset_cloud_status_string(asset)});
+        NSString *msg = writeErr ? writeErr.localizedDescription : @"unknown write error";
+        return json_from_object(@{@"error": [NSString stringWithFormat:@"write failed: %@", msg], @"cloud": asset_cloud_status_string(asset)});
     }
 
     NSNumber *fileSize = nil;
@@ -345,6 +350,10 @@ char *photos_export_original_json(const char *asset_id, const char *output_dir,
     NSString *nsOutputDir = [NSString stringWithUTF8String:output_dir];
     if (!nsAssetId || !nsOutputDir) return json_from_object(make_error_dict(@"invalid UTF-8 in arguments"));
 
+    if (!ensure_directory(nsOutputDir)) {
+        return json_from_object(make_error_dict(@"failed to create output directory"));
+    }
+
     PHFetchResult<PHAsset *> *fetch = [PHAsset fetchAssetsWithLocalIdentifiers:@[nsAssetId] options:nil];
     if (fetch.count == 0) return json_from_object(make_error_dict(@"asset not found"));
 
@@ -382,7 +391,7 @@ char *photos_export_original_json(const char *asset_id, const char *output_dir,
     }
 
     if (writeErr) {
-        return json_from_object(@{@"error": @"write failed", @"cloud": asset_cloud_status_string(asset)});
+        return json_from_object(@{@"error": [NSString stringWithFormat:@"write failed: %@", writeErr.localizedDescription], @"cloud": asset_cloud_status_string(asset)});
     }
 
     NSString *writtenFilename = [filepath lastPathComponent];