fix(upload): two-phase UI — uploading bar then 'processing' spinner

XHR's upload.progress event only tracks browser→server byte transfer. It
fires 100% the moment the multipart body has been pushed, but at that
point our route handler hasn't even started streaming the files into
Appwrite Storage yet. A 200MB upload completes the network phase fast,
then sits 30-60 seconds while the server does sequential storage.createFile
+ tablesDB.createRow per file. The UI was stuck on '100%' the whole time,
making it look frozen.

Switched the form to a discriminated phase state:
  idle → uploading (real bytes %) → processing (full bar + spinner)
       → idle (success/fail)

Listening on xhr.upload's own load event flips us to 'processing' the
instant the body is done. The outer xhr.load fires when the route handler
responds with JSON — that's when we toast + router.refresh().

User now sees: bar fills, then 'Sunucu Appwrite'a yazıyor — büyük dosyalar
30-60 sn sürebilir' message until the response comes back. No more
mystery wait.

src/app/(dashboard)/jobs/[jobId]/components/job-files-panel.tsx

@@ -64,23 +64,26 @@ export function JobFilesPanel({
 const MAX_FILE_BYTES = 200 * 1024 * 1024;
 const MAX_BATCH_BYTES = 200 * 1024 * 1024; // proxy cap; one large file fills the whole batch
 
+type UploadPhase = "idle" | "uploading" | "processing";
+
 function UploadForm({ jobId }: { jobId: string }) {
   const router = useRouter();
   const inputRef = useRef<HTMLInputElement>(null);
   const xhrRef = useRef<XMLHttpRequest | null>(null);
   const [selected, setSelected] = useState<File[]>([]);
-  const [uploading, setUploading] = useState(false);
+  const [phase, setPhase] = useState<UploadPhase>("idle");
   const [progress, setProgress] = useState(0); // 0–100
 
   const totalBytes = selected.reduce((s, f) => s + f.size, 0);
   const overSize = selected.find((f) => f.size > MAX_FILE_BYTES);
   const overBatch = totalBytes > MAX_BATCH_BYTES;
   const blocked = Boolean(overSize) || overBatch;
+  const busy = phase !== "idle";
 
   function reset() {
     setSelected([]);
     setProgress(0);
-    setUploading(false);
+    setPhase("idle");
     if (inputRef.current) inputRef.current.value = "";
   }
 
@@ -91,16 +94,24 @@ function UploadForm({ jobId }: { jobId: string }) {
 
     const xhr = new XMLHttpRequest();
     xhrRef.current = xhr;
-    setUploading(true);
+    setPhase("uploading");
     setProgress(0);
 
     xhr.upload.addEventListener("progress", (e) => {
       if (!e.lengthComputable) return;
-      setProgress(Math.round((e.loaded / e.total) * 100));
+      const pct = Math.round((e.loaded / e.total) * 100);
+      setProgress(pct);
+    });
+
+    // The browser has finished pushing bytes; the server is now writing to
+    // Appwrite. Flip to "processing" so the user sees something is still
+    // happening (large files take 30-60s to land in Storage).
+    xhr.upload.addEventListener("load", () => {
+      setPhase("processing");
+      setProgress(100);
     });
 
     xhr.addEventListener("load", () => {
-      setUploading(false);
       let payload: { ok?: boolean; uploaded?: number; error?: string } = {};
       try {
         payload = JSON.parse(xhr.responseText);
@@ -113,18 +124,19 @@ function UploadForm({ jobId }: { jobId: string }) {
         router.refresh();
       } else {
         toast.error(payload.error || `Yükleme başarısız (HTTP ${xhr.status}).`);
+        setPhase("idle");
         setProgress(0);
       }
     });
 
     xhr.addEventListener("error", () => {
-      setUploading(false);
+      setPhase("idle");
       setProgress(0);
       toast.error("Ağ hatası. Tekrar deneyin.");
     });
 
     xhr.addEventListener("abort", () => {
-      setUploading(false);
+      setPhase("idle");
       setProgress(0);
       toast.message("Yükleme iptal edildi.");
     });
@@ -157,7 +169,7 @@ function UploadForm({ jobId }: { jobId: string }) {
           variant="outline"
           size="sm"
           onClick={() => inputRef.current?.click()}
-          disabled={uploading}
+          disabled={busy}
         >
           <Upload className="size-4" />
           Dosya seç
@@ -181,10 +193,15 @@ function UploadForm({ jobId }: { jobId: string }) {
             "Tarama (STL/OBJ), görsel veya PDF — max 200MB / dosya"
           )}
         </span>
-        {uploading ? (
+        {phase === "uploading" ? (
           <Button type="button" size="sm" variant="outline" onClick={cancelUpload}>
             İptal
           </Button>
+        ) : phase === "processing" ? (
+          <Button type="button" size="sm" variant="outline" disabled>
+            <Loader2 className="size-4 animate-spin" />
+            İşleniyor
+          </Button>
         ) : (
           <Button
             type="button"
@@ -197,7 +214,7 @@ function UploadForm({ jobId }: { jobId: string }) {
           </Button>
         )}
       </div>
-      {uploading && (
+      {phase === "uploading" && (
         <div className="flex items-center gap-3">
           <Progress value={progress} className="flex-1" />
           <span className="text-muted-foreground min-w-[3rem] text-right text-xs tabular-nums">
@@ -205,6 +222,15 @@ function UploadForm({ jobId }: { jobId: string }) {
           </span>
         </div>
       )}
+      {phase === "processing" && (
+        <div className="flex items-center gap-3">
+          <Progress value={100} className="flex-1" />
+          <span className="text-muted-foreground flex items-center gap-1.5 text-xs">
+            <Loader2 className="size-3 animate-spin" />
+            Sunucu Appwrite&apos;a yazıyor — büyük dosyalar 30-60 sn sürebilir
+          </span>
+        </div>
+      )}
     </div>
   );
 }