feat(bridge): establish local pi status bridge

Deliver the initial local bridge, Noctalia v4/v5 adapters, desktop client, service unit, tests, and implementation documentation for persistent Pi status and control.

src/bridge/service.js

@@ -0,0 +1,88 @@
+import path from "node:path";
+import { createAgentRegistry, UnknownAgentError } from "./agent-registry.js";
+import { startPiRpcAdapter } from "./pi-rpc-adapter.js";
+import { ProtocolError } from "../protocol/index.js";
+import { createRuntimePaths, startBridgeServer } from "./runtime.js";
+
+export async function startBridgeService({
+	homeWorktree,
+	runtimeDir,
+	sessionRoot,
+	startAdapter = startPiRpcAdapter,
+	processAlive,
+	maxFrameBytes,
+}) {
+	const paths = await createRuntimePaths(runtimeDir);
+	const registry = createAgentRegistry({
+		homeWorktree,
+		sessionRoot: sessionRoot ?? path.join(paths.directory, "sessions"),
+		startAdapter,
+	});
+
+	const dispatch = async (request) => {
+		try {
+			switch (request.op) {
+				case "list_agents":
+					return { agents: registry.listAgents() };
+				case "list_directories":
+					return { directories: await registry.listDirectories() };
+				case "select_agent":
+					return {
+						agent: await registry.selectWorktree(request.payload.worktreePath),
+					};
+				case "subscribe":
+					return {
+						events: registry.eventsAfter(
+							request.agentId,
+							request.payload.cursor ?? 0,
+						),
+					};
+				case "retry":
+					return { agent: await registry.retry(request.agentId) };
+				case "restart":
+					return { agent: await registry.restart(request.agentId) };
+				case "list_sessions":
+					return { sessions: await registry.listSessions(request.agentId) };
+				default:
+					return registry.route(request.agentId, request.op, request.payload);
+			}
+		} catch (error) {
+			if (error instanceof UnknownAgentError)
+				throw new ProtocolError("unknown_agent", error.message);
+			throw error;
+		}
+	};
+
+	const server = await startBridgeServer({
+		runtimeDir,
+		handleRequest: dispatch,
+		subscribe: (request, notify) => {
+			const subscription = registry.subscribe(
+				request.agentId,
+				request.payload.cursor ?? 0,
+				notify,
+			);
+			return {
+				result: { events: subscription.events },
+				unsubscribe: subscription.unsubscribe,
+			};
+		},
+		...(processAlive ? { processAlive } : {}),
+		...(maxFrameBytes ? { maxFrameBytes } : {}),
+	});
+	try {
+		await registry.start();
+	} catch (error) {
+		await server.close();
+		throw error;
+	}
+
+	return {
+		socketPath: server.socketPath,
+		listAgents: () => registry.listAgents(),
+		async close() {
+			await registry.stop();
+			await server.close();
+		},
+	};
+}