Extract adapter registry across CLI, server, and UI

Refactor monolithic heartbeat service, AgentConfigForm, and CLI
heartbeat-run into a proper adapter registry pattern. Each adapter
type (process, claude-local, codex-local, http) gets its own module
with server-side execution logic, CLI invocation, and UI config form.
Significantly reduces file sizes and enables adding new adapters
without touching core code.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli/src/adapters/registry.ts

@@ -0,0 +1,13 @@
+import type { CLIAdapterModule } from "./types.js";
+import { claudeLocalCLIAdapter } from "./claude-local/index.js";
+import { codexLocalCLIAdapter } from "./codex-local/index.js";
+import { processCLIAdapter } from "./process/index.js";
+import { httpCLIAdapter } from "./http/index.js";
+
+const adaptersByType = new Map<string, CLIAdapterModule>(
+  [claudeLocalCLIAdapter, codexLocalCLIAdapter, processCLIAdapter, httpCLIAdapter].map((a) => [a.type, a]),
+);
+
+export function getCLIAdapter(type: string): CLIAdapterModule {
+  return adaptersByType.get(type) ?? processCLIAdapter;
+}