fix: restrict file attachments to images only

The OpenClaw gateway only supports image attachments in chat.send;
non-image files were silently dropped, confusing users (fixes #24).

- Filter non-image files in addFiles handler
- Update file input accept to image/* only
- Remove unused fileToBase64 helper
- Update i18n labels from 'Attach file' to 'Attach image' (all 8 langs)

Fixes #24

src/components/ChatInput.tsx

@@ -38,19 +38,6 @@ interface Props {
 const MAX_BASE64_CHARS = 300 * 1024; // ~225KB real, well under 512KB WS limit (JSON overhead + base64 bloat)
 const MAX_IMAGE_PIXELS = 1280; // Max dimension for resize
 
-function fileToBase64(file: File): Promise<string> {
-  return new Promise((resolve, reject) => {
-    const reader = new FileReader();
-    reader.onload = () => {
-      const dataUrl = reader.result as string;
-      const base64 = dataUrl.split(',')[1] || '';
-      resolve(base64);
-    };
-    reader.onerror = reject;
-    reader.readAsDataURL(file);
-  });
-}
-
 function compressImage(file: File, maxBase64Chars: number): Promise<{ base64: string; mimeType: string }> {
   return new Promise((resolve, reject) => {
     const img = new Image();
@@ -184,24 +171,18 @@ export function ChatInput({ onSend, onNewSession, onAbort, isGenerating, disable
     const newFiles: FileAttachment[] = [];
     for (const file of Array.from(fileList)) {
       if (file.size > 20 * 1024 * 1024) continue; // 20MB max
-      const isImage = file.type.startsWith('image/');
-      let base64: string;
-      let mimeType: string;
-      if (isImage) {
+      // Only images are supported — the OpenClaw gateway drops non-image attachments
+      if (!file.type.startsWith('image/')) continue;
       // Compress images to fit WS payload limit
       const compressed = await compressImage(file, MAX_BASE64_CHARS);
-        base64 = compressed.base64;
-        mimeType = compressed.mimeType;
-      } else {
-        base64 = await fileToBase64(file);
-        mimeType = file.type || 'application/octet-stream';
-      }
+      const base64 = compressed.base64;
+      const mimeType = compressed.mimeType;
       newFiles.push({
         id: `${Date.now()}-${Math.random().toString(36).slice(2, 8)}`,
         file,
         base64,
         mimeType,
-        preview: isImage ? `data:${mimeType};base64,${base64}` : undefined,
+        preview: `data:${mimeType};base64,${base64}`,
       });
     }
     setFiles(prev => [...prev, ...newFiles]);
@@ -418,7 +399,7 @@ export function ChatInput({ onSend, onNewSession, onAbort, isGenerating, disable
               multiple
               className="hidden"
               onChange={(e) => { if (e.target.files) addFiles(e.target.files); e.target.value = ''; }}
-              accept="image/*,.pdf,.txt,.md,.json,.csv,.log,.py,.js,.ts,.tsx,.jsx,.html,.css,.yaml,.yml,.xml,.sql,.sh,.env,.toml"
+              accept="image/*"
             />
 
             <textarea

src/lib/i18n.ts

@@ -49,7 +49,7 @@ const en = {
   'chat.loadingHistory': 'Loading messages…',
   'chat.inputPlaceholder': 'Type a message…',
   'chat.inputLabel': 'Message',
-  'chat.attachFile': 'Attach file',
+  'chat.attachFile': 'Attach image',
   'chat.send': 'Send',
   'chat.stop': 'Stop',
   'chat.showPreview': 'Preview markdown',
@@ -245,7 +245,7 @@ const fr: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'Chargement des messages…',
   'chat.inputPlaceholder': 'Tapez un message…',
   'chat.inputLabel': 'Message',
-  'chat.attachFile': 'Joindre un fichier',
+  'chat.attachFile': 'Joindre une image',
   'chat.send': 'Envoyer',
   'chat.stop': 'Arrêter',
   'chat.showPreview': 'Aperçu markdown',
@@ -428,7 +428,7 @@ const es: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'Cargando mensajes…',
   'chat.inputPlaceholder': 'Escribe un mensaje…',
   'chat.inputLabel': 'Mensaje',
-  'chat.attachFile': 'Adjuntar archivo',
+  'chat.attachFile': 'Adjuntar imagen',
   'chat.send': 'Enviar',
   'chat.stop': 'Detener',
   'chat.showPreview': 'Vista previa markdown',
@@ -613,7 +613,7 @@ const de: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'Nachrichten werden geladen…',
   'chat.inputPlaceholder': 'Nachricht eingeben…',
   'chat.inputLabel': 'Nachricht',
-  'chat.attachFile': 'Datei anhängen',
+  'chat.attachFile': 'Bild anhängen',
   'chat.send': 'Senden',
   'chat.stop': 'Stoppen',
   'chat.showPreview': 'Markdown-Vorschau',
@@ -796,7 +796,7 @@ const ja: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'メッセージを読み込み中…',
   'chat.inputPlaceholder': 'メッセージを入力…',
   'chat.inputLabel': 'メッセージ',
-  'chat.attachFile': 'ファイルを添付',
+  'chat.attachFile': '画像を添付',
   'chat.send': '送信',
   'chat.stop': '停止',
   'chat.showPreview': 'Markdownプレビュー',
@@ -979,7 +979,7 @@ const pt: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'Carregando mensagens…',
   'chat.inputPlaceholder': 'Digite uma mensagem…',
   'chat.inputLabel': 'Mensagem',
-  'chat.attachFile': 'Anexar arquivo',
+  'chat.attachFile': 'Anexar imagem',
   'chat.send': 'Enviar',
   'chat.stop': 'Parar',
   'chat.showPreview': 'Pré-visualizar markdown',
@@ -1162,7 +1162,7 @@ const zh: Record<keyof typeof en, string> = {
   'chat.loadingHistory': '加载消息中…',
   'chat.inputPlaceholder': '输入消息…',
   'chat.inputLabel': '消息',
-  'chat.attachFile': '添加附件',
+  'chat.attachFile': '添加图片',
   'chat.send': '发送',
   'chat.stop': '停止',
   'chat.showPreview': '预览 Markdown',
@@ -1345,7 +1345,7 @@ const it: Record<keyof typeof en, string> = {
   'chat.loadingHistory': 'Caricamento messaggi…',
   'chat.inputPlaceholder': 'Scrivi un messaggio…',
   'chat.inputLabel': 'Messaggio',
-  'chat.attachFile': 'Allega file',
+  'chat.attachFile': 'Allega immagine',
   'chat.send': 'Invia',
   'chat.stop': 'Ferma',
   'chat.showPreview': 'Anteprima markdown',