feat: agent summoning system, todo improvements, security fixes, double-execution bug fix

- Add summon/retrieve tools for spawning child agents in new tabs
  - summon: non-blocking, returns agent_id immediately
  - retrieve: blocking, waits for child to finish, returns result
  - Child tools are intersected with parent permissions (no privilege escalation)
  - Working directory validated to stay within workspace
  - Abort controller stops orphaned agents on tab close
- Rename task_list tool to todo with comprehensive usage guidance in system prompt
- Rename PermissionLog.svelte to ToolPermissions.svelte
- Add 'Summon agents' toggle to tool permissions UI
- Redesign TaskListPanel with DaisyUI checkboxes (indeterminate for in-progress)
- Remove 'blocked' status from task system
- Add tab-created WebSocket event for child agent tab visibility
- Add HMR cleanup for WebSocket connections (close stale connections on hot reload)
- Fix ensureAssistantMessage to not throw on closed tabs
- Fix double tool execution: remove execute from AI SDK tool() in registry.ts
  (agent.ts already executes tools manually via executeToolWithStreaming)
- Fix all pre-existing test failures (missing mocks, stale API signatures)
- Add debug info to copy button (tab ID, injected skills, all tab IDs)
- Add tab ID and tools to conversation copy output

1 files changed, 41 insertions, 0 deletions

diff --git a/packages/core/src/tools/retrieve.ts b/packages/core/src/tools/retrieve.ts
new file mode 100644
index 0000000..93f4c89
--- /dev/null
+++ b/packages/core/src/tools/retrieve.ts
@@ -0,0 +1,41 @@
+import { z } from "zod";
+import type { ToolDefinition } from "../types/index.js";
+
+export interface RetrieveCallbacks {
+	getResult(
+		agentId: string,
+	): Promise<{ status: "done"; result: string } | { status: "error"; error: string }>;
+}
+
+export function createRetrieveTool(callbacks: RetrieveCallbacks): ToolDefinition {
+	return {
+		name: "retrieve",
+		description: [
+			"Wait for a child agent to finish and retrieve its result. This tool BLOCKS until the child completes.",
+			"",
+			"Pass the agent_id returned by the summon tool. Once the child finishes, its final output is returned.",
+			"If the child encountered an error, the error message is returned instead.",
+			"",
+			"Typical usage:",
+			'  1. summon({ task: "...", tools: [...] })  -> get agent_id',
+			"  2. ... do other work or summon more agents ...",
+			'  3. retrieve({ agent_id: "..." })  -> blocks until done, returns result',
+		].join("\n"),
+		parameters: z.object({
+			agent_id: z.string().describe("The agent_id returned by a previous summon call."),
+		}),
+		execute: async (args: Record<string, unknown>): Promise<string> => {
+			const agentId = args.agent_id as string;
+
+			try {
+				const outcome = await callbacks.getResult(agentId);
+				if (outcome.status === "done") {
+					return ["<agent_result>", outcome.result, "</agent_result>"].join("\n");
+				}
+				return `Agent error: ${outcome.error}`;
+			} catch (err) {
+				return `Error retrieving result: ${err instanceof Error ? err.message : String(err)}`;
+			}
+		},
+	};
+}