feat: make each plugin an npm workspace built by a termix-plugin CLI

scripts/build-plugins.cjs

@@ -0,0 +1,58 @@
+/**
+ * Builds every plugin workspace, then stages the result in dist/plugins.
+ *
+ * getBundledPluginsDir() in src/backend/plugins/paths.ts resolves
+ * dist/backend/backend/plugins -> dist/plugins, which is where this writes.
+ * Only what a server needs at runtime is copied: the manifest, the built
+ * bundles, locales and migrations. Source and tests stay out of the image.
+ */
+
+const fs = require("node:fs");
+const path = require("node:path");
+const { execFileSync } = require("node:child_process");
+
+const root = path.resolve(__dirname, "..");
+const source = path.join(root, "plugins");
+const destination = path.join(root, "dist", "plugins");
+const cli = path.join(root, "packages", "plugin-sdk", "cli", "index.mjs");
+
+const SHIPPED = ["manifest.json", "dist", "locales", "migrations", "README.md"];
+
+if (!fs.existsSync(source)) {
+  console.log("No plugins/ directory, nothing to bundle.");
+  process.exit(0);
+}
+
+const pluginIds = fs
+  .readdirSync(source, { withFileTypes: true })
+  .filter((entry) => entry.isDirectory())
+  .filter((entry) =>
+    fs.existsSync(path.join(source, entry.name, "manifest.json")),
+  )
+  .map((entry) => entry.name);
+
+fs.rmSync(destination, { recursive: true, force: true });
+
+for (const id of pluginIds) {
+  const pluginDir = path.join(source, id);
+
+  execFileSync(process.execPath, [cli, "build"], {
+    cwd: pluginDir,
+    stdio: "inherit",
+  });
+
+  const built = path.join(pluginDir, "dist", "backend.js");
+  if (!fs.existsSync(built)) {
+    throw new Error(`${id} produced no dist/backend.js`);
+  }
+
+  const outDir = path.join(destination, id);
+  fs.mkdirSync(outDir, { recursive: true });
+  for (const entry of SHIPPED) {
+    const from = path.join(pluginDir, entry);
+    if (!fs.existsSync(from)) continue;
+    fs.cpSync(from, path.join(outDir, entry), { recursive: true });
+  }
+}
+
+console.log(`Bundled ${pluginIds.length} plugin(s): ${pluginIds.join(", ")}`);