Truncate voice-transcript echo so Telegram doesn't reject long messages

The bot re-emits the transcript back to the owner as a preview
(`🎤 …`). Telegram's sendMessage caps at 4096 chars, so a long audio
message crashed the handler with a 400. Trim the echo to 200 chars
with an ellipsis; the agent still receives the full transcript via
result.input.text.

CLAUDE.md

@@ -0,0 +1,3 @@
+<!-- release-notes-config
+declined: true
+-->

src/telegram/bridge.test.ts

@@ -262,6 +262,22 @@ describe("registerBridge", () => {
     );
   });
 
+  it("echoes a truncated transcript but sends the full text to the agent", async () => {
+    const long = "a".repeat(5000);
+    const transcriber = { transcribe: async () => long };
+    const h = harness({ debounceMs: 5, transcriber });
+    const voiceUpdate = textUpdate("");
+    delete (voiceUpdate.message as { text?: string }).text;
+    (voiceUpdate.message as { voice?: unknown }).voice = { file_id: "v1", file_unique_id: "u", duration: 3, mime_type: "audio/ogg" };
+    await h.bot.handleUpdate(voiceUpdate);
+    const echoed = h.texts().find((t) => t.startsWith("🎤 "));
+    expect(echoed).toBeDefined();
+    // Emoji + space + 199 chars + ellipsis = 202 code points.
+    expect(Array.from(echoed as string)).toHaveLength(202);
+    expect((echoed as string).endsWith("…")).toBe(true);
+    await vi.waitFor(() => expect(h.host.sent).toEqual([{ text: long, images: undefined }]));
+  });
+
   it("drops buffered messages when /new starts a fresh session", async () => {
     const h = harness({ debounceMs: 100 });
     await h.bot.handleUpdate(textUpdate("hold this thought"));

src/telegram/bridge.ts

@@ -16,6 +16,9 @@ import type { Outbound } from "./outbound.js";
 /** How long we wait after the last message before delivering the merged batch to the agent. */
 const DEFAULT_DEBOUNCE_MS = 600;
 
+/** Longest transcript we echo back to the owner before truncating with an ellipsis. Telegram caps sendMessage at 4096 chars. */
+const MAX_TRANSCRIPT_ECHO_CHARS = 200;
+
 export type HostLike = Pick<AgentHost, "busy" | "send" | "abort" | "newSession" | "compact" | "status" | "subscribe">;
 export type SchedulerLike = Pick<Scheduler, "list" | "delete">;
 
@@ -211,7 +214,7 @@ export function registerBridge(deps: BridgeDeps): void {
         botUserId: bot.botInfo?.id,
       });
       for (const note of result.notes) await ctx.reply(note);
-      if (result.transcript) await ctx.reply(`🎤 ${result.transcript}`);
+      if (result.transcript) await ctx.reply(`🎤 ${truncateForEcho(result.transcript)}`);
       if (!result.input) {
         if (result.notes.length === 0) await ctx.reply("I can handle text, photos, voice notes, and files.");
         return;
@@ -282,3 +285,9 @@ export async function downloadFile(
 function errorText(err: unknown): string {
   return err instanceof Error ? err.message : String(err);
 }
+
+export function truncateForEcho(text: string): string {
+  const chars = Array.from(text);
+  if (chars.length <= MAX_TRANSCRIPT_ECHO_CHARS) return text;
+  return `${chars.slice(0, MAX_TRANSCRIPT_ECHO_CHARS - 1).join("")}…`;
+}