Add tea_issues tool for listing GitHub issues

.opencode/tools/tea-issues.ts

@@ -0,0 +1,11 @@
+import { tool } from "@opencode-ai/plugin"
+import path from "path"
+
+export default tool({
+  description: "List all issues in the project using tea CLI",
+  args: {},
+  async execute(args, context) {
+    const result = await Bun.$`tea issues list`.text()
+    return result.trim()
+  },
+})