fix(agent): stop tool thrash after writes and log rounds

Cap get_api_docs, break duplicate tool rounds, force a reply after
successful writes, and log each tool call so limit hits are diagnosable.

src/modules/agent/assistant-chat-storage.ts

@@ -4,6 +4,7 @@ export type AssistantChatMessage = {
   role: "user" | "assistant";
   content: string;
   imageUrl?: string;
+  toolCalls?: Array<{ name: string; status: number }>;
 };
 
 const STORAGE_VERSION = "v2";
@@ -19,6 +20,14 @@ function isValidMessage(value: unknown): value is AssistantChatMessage {
   if (row.role !== "user" && row.role !== "assistant") return false;
   if (typeof row.content !== "string" || row.content.trim().length === 0) return false;
   if (row.imageUrl !== undefined && typeof row.imageUrl !== "string") return false;
+  if (row.toolCalls !== undefined) {
+    if (!Array.isArray(row.toolCalls)) return false;
+    for (const call of row.toolCalls) {
+      if (!call || typeof call !== "object") return false;
+      const entry = call as Record<string, unknown>;
+      if (typeof entry.name !== "string" || typeof entry.status !== "number") return false;
+    }
+  }
   return true;
 }