fix: Catch preflight errors on file upload (#212)

* Catch preflight errors on js api

* ts error fix

* Throw error instead of return statement

* Add second reaction for uploader

---------

Co-authored-by: Mert Kirbuga <mert.kirbuga@backlight.co>

source/session.ts

@@ -1092,7 +1092,7 @@ export class Session<
         },
       });
 
-      uploader.start();
+      uploader.start().catch(reject);
     });
   }
 }

source/uploader.ts

@@ -177,7 +177,14 @@ export class Uploader<TEntityTypeMap extends Record<string, any>> {
   /** Initiate upload. Promise is resolved once preflight is complete and upload started. */
   async start() {
     logger.debug("Upload starting", this.componentId);
-    await this.uploadPreflight();
+    try {
+      await this.uploadPreflight();
+    } catch (error) {
+      if (this.onError) {
+        this.onError(error as Error);
+      }
+      throw error;
+    }
     if (!this.uploadMetadata) {
       throw new Error("Failed to get upload metadata");
     }