feat(FN-3332): add droid runtime plugin with event bridge and process manag

The merge delivers a new `fusion-plugin-droid-runtime` plugin providing a full MCP server and runtime adapter for droid-based agents, with event bridging, process management, tool mapping, and a prompt builder. It also adds agent delegation and org hierarchy tools to the pi extension, while fixing a

Fusion-Task-Id: FN-3332

plugins/fusion-plugin-droid-runtime/src/index.ts

@@ -0,0 +1,58 @@
+import { definePlugin } from "@fusion/plugin-sdk";
+import type { FusionPlugin, PluginRuntimeFactory, PluginRuntimeManifestMetadata } from "@fusion/plugin-sdk";
+import { resolveCliSettings } from "./cli-spawn.js";
+import { DroidRuntimeAdapter } from "./runtime-adapter.js";
+
+export const DROID_RUNTIME_ID = "droid";
+const DROID_RUNTIME_VERSION = "0.1.0";
+
+export const droidRuntimeMetadata: PluginRuntimeManifestMetadata = {
+  runtimeId: DROID_RUNTIME_ID,
+  name: "Droid Runtime",
+  description: "Drives the Droid CLI for Fusion agents",
+  version: DROID_RUNTIME_VERSION,
+};
+
+export const droidRuntimeFactory: PluginRuntimeFactory = async (ctx) =>
+  new DroidRuntimeAdapter(ctx.settings as Record<string, unknown> | undefined);
+
+const plugin: FusionPlugin = definePlugin({
+  manifest: {
+    id: "fusion-plugin-droid-runtime",
+    name: "Droid Runtime Plugin",
+    version: DROID_RUNTIME_VERSION,
+    description: "Drives the Droid CLI for Fusion agents",
+    runtime: droidRuntimeMetadata,
+  },
+  state: "installed",
+  hooks: {
+    onLoad: (ctx) => {
+      const settings = resolveCliSettings(ctx.settings as Record<string, unknown>);
+      ctx.logger.info(`Droid Runtime Plugin loaded — binary=${settings.binaryPath} model=${settings.model ?? "(default)"}`);
+    },
+  },
+  uiSlots: [
+    { slotId: "settings-provider-card", label: "Droid CLI Provider", componentPath: "./components/settings-provider-card.js" },
+    { slotId: "onboarding-provider-card", label: "Droid CLI Provider", componentPath: "./components/onboarding-provider-card.js" },
+    { slotId: "onboarding-setup-help", label: "Droid CLI Setup Help", componentPath: "./components/onboarding-setup-help.js" },
+    { slotId: "post-onboarding-recommendation", label: "Droid CLI Recommendation", componentPath: "./components/post-onboarding-recommendation.js" }
+  ],
+  runtime: {
+    metadata: droidRuntimeMetadata,
+    factory: droidRuntimeFactory,
+  },
+});
+
+export default plugin;
+export { DroidRuntimeAdapter };
+export { probeDroidBinary } from "./probe.js";
+export type { DroidBinaryStatus } from "./probe.js";
+export { streamViaCli } from "./provider.js";
+export {
+  discoverDroidModels,
+  validateCliPresenceAsync,
+  validateCliAuthAsync,
+  killAllProcesses,
+} from "./process-manager.js";
+export { getCustomToolDefs, toolsFromContext, writeMcpConfig } from "./mcp-config.js";
+export type { McpToolDef } from "./mcp-config.js";