fix: sanitize thinking blocks for GitHub Copilot Claude models (openclaw#19459) thanks @jackheuberger

Verified:
- pnpm build
- pnpm check
- pnpm test:macmini

Co-authored-by: jackheuberger <12731288+jackheuberger@users.noreply.github.com>
Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>

src/agents/pi-embedded-runner/run/attempt.ts

@@ -94,6 +94,7 @@ import {
   buildEmbeddedSystemPrompt,
   createSystemPromptOverride,
 } from "../system-prompt.js";
+import { dropThinkingBlocks } from "../thinking.js";
 import { installToolResultContextGuard } from "../tool-result-context-guard.js";
 import { splitSdkTools } from "../tool-split.js";
 import { describeUnknownError, mapThinkingLevel } from "../utils.js";
@@ -652,6 +653,30 @@ export async function runEmbeddedAttempt(
         });
         activeSession.agent.streamFn = cacheTrace.wrapStreamFn(activeSession.agent.streamFn);
       }
+
+      // Copilot/Claude can reject persisted `thinking` blocks (e.g. thinkingSignature:"reasoning_text")
+      // on *any* follow-up provider call (including tool continuations). Wrap the stream function
+      // so every outbound request sees sanitized messages.
+      if (transcriptPolicy.dropThinkingBlocks) {
+        const inner = activeSession.agent.streamFn;
+        activeSession.agent.streamFn = (model, context, options) => {
+          const ctx = context as unknown as { messages?: unknown };
+          const messages = ctx?.messages;
+          if (!Array.isArray(messages)) {
+            return inner(model, context, options);
+          }
+          const sanitized = dropThinkingBlocks(messages as unknown as AgentMessage[]) as unknown;
+          if (sanitized === messages) {
+            return inner(model, context, options);
+          }
+          const nextContext = {
+            ...(context as unknown as Record<string, unknown>),
+            messages: sanitized,
+          } as unknown;
+          return inner(model, nextContext as typeof context, options);
+        };
+      }
+
       if (anthropicPayloadLogger) {
         activeSession.agent.streamFn = anthropicPayloadLogger.wrapStreamFn(
           activeSession.agent.streamFn,
@@ -945,7 +970,7 @@ export async function runEmbeddedAttempt(
             sessionManager.resetLeaf();
           }
           const sessionContext = sessionManager.buildSessionContext();
-          const sanitizedOrphan = transcriptPolicy.normalizeAntigravityThinkingBlocks
+          const sanitizedOrphan = transcriptPolicy.sanitizeThinkingSignatures
             ? sanitizeAntigravityThinkingBlocks(sessionContext.messages)
             : sessionContext.messages;
           activeSession.agent.replaceMessages(sanitizedOrphan);