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

packages/droid-cli/README.md

@@ -1,25 +1,8 @@
 # @fusion/droid-cli
 
-First-party Fusion pi extension package that routes pi provider requests through the `droid` CLI subprocess using stream-json NDJSON.
+Compatibility shim package for Fusion's Droid integration.
 
-## Provider
+Runtime/provider implementation now lives in:
+- `@fusion-plugin-examples/droid-runtime` (`plugins/fusion-plugin-droid-runtime`)
 
-- Provider ID: `droid-cli`
-- Binary: `droid` (must be installed and authenticated on PATH)
-- Registration: package extension entrypoint in `index.ts`
-
-## Capabilities
-
-- Subprocess streaming bridge for text/thinking/tool events
-- Model auto-discovery from Droid CLI at provider startup with in-process caching
-- Session resume support (`--resume` / `--session-id`) to avoid replaying prior turns
-- MCP schema bridge for exposing pi custom tools as schema-only definitions
-- Tool mapping and break-early control so pi remains the tool executor
-- Thinking effort mapping from pi reasoning options to Droid CLI flags
-
-## Development
-
-```bash
-pnpm --filter @fusion/droid-cli test
-pnpm --filter @fusion/droid-cli exec tsc --noEmit
-```
+This package preserves the historical pi extension entrypoint and delegates to the plugin-owned implementation so existing imports continue to work.

packages/droid-cli/index.ts

@@ -1,18 +1,18 @@
 import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
-import { streamViaCli } from "./src/provider.js";
+import { streamViaCli } from "../../plugins/fusion-plugin-droid-runtime/src/provider.js";
 import {
+  discoverDroidModels,
   validateCliPresenceAsync,
   validateCliAuthAsync,
   killAllProcesses,
-  discoverDroidModels,
-} from "./src/process-manager.js";
+} from "../../plugins/fusion-plugin-droid-runtime/src/process-manager.js";
 import { createHash } from "node:crypto";
 import {
   getCustomToolDefs,
   toolsFromContext,
   writeMcpConfig,
   type McpToolDef,
-} from "./src/mcp-config.js";
+} from "../../plugins/fusion-plugin-droid-runtime/src/mcp-config.js";
 
 process.on("exit", killAllProcesses);
 
@@ -117,7 +117,11 @@ export default function (pi: ExtensionAPI) {
             pi,
             (context as { tools?: ReadonlyArray<{ name: string; description: string; parameters: Record<string, unknown> }> }).tools,
           );
-          return streamViaCli(model, context, { ...options, mcpConfigPath: configPath });
+          return streamViaCli(
+            model,
+            context as never,
+            { ...(options ?? {}), mcpConfigPath: configPath } as never,
+          );
         },
       });
     } catch (err) {

packages/droid-cli/package.json

@@ -25,6 +25,9 @@
     "@mariozechner/pi-ai": "*",
     "@mariozechner/pi-coding-agent": "*"
   },
+  "dependencies": {
+    "@fusion-plugin-examples/droid-runtime": "workspace:*"
+  },
   "devDependencies": {
     "@types/node": "^22.0.0",
     "typescript": "^5.7.0",

packages/droid-cli/src/__tests__/provider.test.ts

@@ -71,16 +71,16 @@ import { streamViaCli } from "../provider";
 describe("provider registration (default export)", () => {
   it("registers provider id droid-cli with deduped discovered models", async () => {
     vi.resetModules();
-    vi.doMock("../../src/provider.js", () => ({
+    vi.doMock("../../../../plugins/fusion-plugin-droid-runtime/src/provider.js", () => ({
       streamViaCli: vi.fn(() => ({ mocked: true })),
     }));
-    vi.doMock("../../src/process-manager.js", () => ({
+    vi.doMock("../../../../plugins/fusion-plugin-droid-runtime/src/process-manager.js", () => ({
       validateCliPresenceAsync: vi.fn(async () => ({ ok: true })),
       validateCliAuthAsync: vi.fn(async () => true),
       killAllProcesses: vi.fn(),
       discoverDroidModels: vi.fn(async () => ["droid-pro", "droid-max", "droid-pro"]),
     }));
-    vi.doMock("../../src/mcp-config.js", () => ({
+    vi.doMock("../../../../plugins/fusion-plugin-droid-runtime/src/mcp-config.js", () => ({
       getCustomToolDefs: vi.fn(() => []),
       toolsFromContext: vi.fn(() => []),
       writeMcpConfig: vi.fn(() => "/tmp/droid-mcp.json"),
@@ -105,9 +105,9 @@ describe("provider registration (default export)", () => {
       "droid-pro",
       "droid-max",
     ]);
-    vi.doUnmock("../../src/provider.js");
-    vi.doUnmock("../../src/process-manager.js");
-    vi.doUnmock("../../src/mcp-config.js");
+    vi.doUnmock("../../../../plugins/fusion-plugin-droid-runtime/src/provider.js");
+    vi.doUnmock("../../../../plugins/fusion-plugin-droid-runtime/src/process-manager.js");
+    vi.doUnmock("../../../../plugins/fusion-plugin-droid-runtime/src/mcp-config.js");
   });
 });