feat(server-v2): add standalone runtime and SDK foundation (#1468)

* feat(server-v2): add standalone runtime and SDK foundation

* docs(server-v2): drop planning task checklists

* build(server-v2): generate OpenAPI and SDK during dev

* build(server-v2): generate API artifacts before builds

* build(server-v2): drop duplicate root SDK generation

* build(app): remove SDK generation hooks

---------

Co-authored-by: src-opn <src-opn@users.noreply.github.com>

apps/server-v2/scripts/watch-openapi.mjs

@@ -0,0 +1,72 @@
+import { spawn } from "node:child_process";
+import { watch } from "node:fs";
+import path from "node:path";
+import process from "node:process";
+import { fileURLToPath } from "node:url";
+
+const scriptDir = path.dirname(fileURLToPath(import.meta.url));
+const packageDir = path.resolve(scriptDir, "..");
+const watchedDir = path.join(packageDir, "src");
+
+let activeChild = null;
+let queued = false;
+let timer = null;
+
+function runGenerate() {
+  if (activeChild) {
+    queued = true;
+    return;
+  }
+
+  activeChild = spawn("bun", ["./scripts/generate-openapi.ts"], {
+    cwd: packageDir,
+    env: process.env,
+    stdio: "inherit",
+  });
+
+  activeChild.once("exit", (code) => {
+    activeChild = null;
+
+    if (code && code !== 0) {
+      process.stderr.write(`[openwork-server-v2] OpenAPI generation failed with exit code ${code}.\n`);
+    }
+
+    if (queued) {
+      queued = false;
+      scheduleGenerate();
+    }
+  });
+}
+
+function scheduleGenerate() {
+  if (timer) {
+    clearTimeout(timer);
+  }
+
+  timer = setTimeout(() => {
+    timer = null;
+    runGenerate();
+  }, 120);
+}
+
+runGenerate();
+
+const watcher = watch(watchedDir, { recursive: true }, (_eventType, filename) => {
+  if (!filename || String(filename).includes(".DS_Store")) {
+    return;
+  }
+
+  scheduleGenerate();
+});
+
+for (const signal of ["SIGINT", "SIGTERM"]) {
+  process.on(signal, () => {
+    watcher.close();
+
+    if (activeChild && activeChild.exitCode === null) {
+      activeChild.kill("SIGTERM");
+    }
+
+    process.exit(0);
+  });
+}