fix(tool-registry): unify task_system default

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/plugin/tool-registry.test.ts

@@ -2,7 +2,7 @@ import { describe, expect, test } from "bun:test"
 import { tool } from "@opencode-ai/plugin"
 
 import type { ToolsRecord } from "./types"
-import { trimToolsToCap } from "./tool-registry"
+import { createToolRegistry, trimToolsToCap } from "./tool-registry"
 
 const fakeTool = tool({
   description: "test tool",
@@ -27,3 +27,57 @@ describe("#given tool trimming prioritization", () => {
     expect(filteredTools).toHaveProperty("read")
   })
 })
+
+describe("#given task_system configuration", () => {
+  test("#when task_system is omitted #then task tools are not registered by default", () => {
+    const result = createToolRegistry({
+      ctx: { directory: "/tmp" } as Parameters<typeof createToolRegistry>[0]["ctx"],
+      pluginConfig: {},
+      managers: {
+        backgroundManager: {},
+        tmuxSessionManager: {},
+        skillMcpManager: {},
+      } as Parameters<typeof createToolRegistry>[0]["managers"],
+      skillContext: {
+        mergedSkills: [],
+        availableSkills: [],
+        browserProvider: "playwright",
+        disabledSkills: new Set(),
+      },
+      availableCategories: [],
+    })
+
+    expect(result.taskSystemEnabled).toBe(false)
+    expect(result.filteredTools).not.toHaveProperty("task_create")
+    expect(result.filteredTools).not.toHaveProperty("task_get")
+    expect(result.filteredTools).not.toHaveProperty("task_list")
+    expect(result.filteredTools).not.toHaveProperty("task_update")
+  })
+
+  test("#when task_system is enabled #then task tools are registered", () => {
+    const result = createToolRegistry({
+      ctx: { directory: "/tmp" } as Parameters<typeof createToolRegistry>[0]["ctx"],
+      pluginConfig: {
+        experimental: { task_system: true },
+      },
+      managers: {
+        backgroundManager: {},
+        tmuxSessionManager: {},
+        skillMcpManager: {},
+      } as Parameters<typeof createToolRegistry>[0]["managers"],
+      skillContext: {
+        mergedSkills: [],
+        availableSkills: [],
+        browserProvider: "playwright",
+        disabledSkills: new Set(),
+      },
+      availableCategories: [],
+    })
+
+    expect(result.taskSystemEnabled).toBe(true)
+    expect(result.filteredTools).toHaveProperty("task_create")
+    expect(result.filteredTools).toHaveProperty("task_get")
+    expect(result.filteredTools).toHaveProperty("task_list")
+    expect(result.filteredTools).toHaveProperty("task_update")
+  })
+})