Fix: Preserve Per-Agent Exec Override After Session Compaction (#15833)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: 9dfe5bdf23
Co-authored-by: napetrov <18015221+napetrov@users.noreply.github.com>
Co-authored-by: steipete <58493+steipete@users.noreply.github.com>
Reviewed-by: @steipete

src/agents/pi-tools-agent-config.e2e.test.ts

@@ -535,4 +535,59 @@ describe("Agent-specific tool filtering", () => {
 
     expect(result?.details.status).toBe("completed");
   });
+
+  it("should apply agent-specific exec host defaults over global defaults", async () => {
+    const cfg: OpenClawConfig = {
+      tools: {
+        exec: {
+          host: "sandbox",
+        },
+      },
+      agents: {
+        list: [
+          {
+            id: "main",
+            tools: {
+              exec: {
+                host: "gateway",
+              },
+            },
+          },
+          {
+            id: "helper",
+          },
+        ],
+      },
+    };
+
+    const mainTools = createOpenClawCodingTools({
+      config: cfg,
+      sessionKey: "agent:main:main",
+      workspaceDir: "/tmp/test-main-exec-defaults",
+      agentDir: "/tmp/agent-main-exec-defaults",
+    });
+    const mainExecTool = mainTools.find((tool) => tool.name === "exec");
+    expect(mainExecTool).toBeDefined();
+    await expect(
+      mainExecTool!.execute("call-main", {
+        command: "echo done",
+        host: "sandbox",
+      }),
+    ).rejects.toThrow("exec host not allowed");
+
+    const helperTools = createOpenClawCodingTools({
+      config: cfg,
+      sessionKey: "agent:helper:main",
+      workspaceDir: "/tmp/test-helper-exec-defaults",
+      agentDir: "/tmp/agent-helper-exec-defaults",
+    });
+    const helperExecTool = helperTools.find((tool) => tool.name === "exec");
+    expect(helperExecTool).toBeDefined();
+    const helperResult = await helperExecTool!.execute("call-helper", {
+      command: "echo done",
+      host: "sandbox",
+      yieldMs: 10,
+    });
+    expect(helperResult?.details.status).toBe("completed");
+  });
 });