Bug Description

When using Amazon Bedrock models, the provider/model callback data string (e.g., mdl_sel_amazon-bedrock/us.anthropic.claude-haiku-4-5-20251001-v1:0) can exceed Telegram's 64-byte callback_data limit. The current code silently skips these buttons with continue, making the model completely unselectable from the Telegram /model picker UI.

Expected Behavior

When the full provider/model callback data exceeds 64 bytes, the code should try a shorter format (e.g., omit the provider prefix: mdl_sel_us.anthropic.claude-haiku-4-5-20251001-v1:0) and only skip if that also exceeds the limit. The callback parser and handler should support both formats.

Actual Behavior

const callbackData = `mdl_sel_${provider}/${model}`;
if (Buffer.byteLength(callbackData, "utf8") > MAX_CALLBACK_DATA_BYTES) continue;
// Button silently dropped — model is unselectable

Impact

Any Bedrock model with a long ID (which is most of them, e.g., global.anthropic.claude-sonnet-4-6, us.anthropic.claude-haiku-4-5-20251001-v1:0) cannot be selected via the Telegram model picker. Users see an incomplete or empty model list.

Suggested Fix

Three changes needed across subagent-registry-*.js, reply-*.js, and pi-embedded-*.js:

1. Button generation — fallback to model-only callback:

- const callbackData = `mdl_sel_${provider}/${model}`;
- if (Buffer.byteLength(callbackData, "utf8") > MAX_CALLBACK_DATA_BYTES) continue;
+ let callbackData = `mdl_sel_${provider}/${model}`;
+ if (Buffer.byteLength(callbackData, "utf8") > MAX_CALLBACK_DATA_BYTES) {
+   callbackData = `mdl_sel_${model}`;
+   if (Buffer.byteLength(callbackData, "utf8") > MAX_CALLBACK_DATA_BYTES) continue;
+ }

2. Callback parser — handle missing provider:

  if (slashIndex > 0 && slashIndex < modelRef.length - 1) return {
    type: "select", provider: modelRef.slice(0, slashIndex), model: modelRef.slice(slashIndex + 1)
  };
+ return { type: "select", provider: "", model: modelRef };

3. Callback handler — support empty provider:

  const { provider, model } = modelCallback;
- text: `/model ${provider}/${model}`
+ const modelArg = provider ? `${provider}/${model}` : model;
+ text: `/model ${modelArg}`

Environment

• OpenClaw: v2026.3.1
• Channel: Telegram
• Provider: Amazon Bedrock