Add @tursodatabase/serverless package

This package is for serverless access to the Turso Cloud using SQL over
HTTP protocol. The purpose of this package is to provide the same
interface as `@tursodatabase/turso`, but for serverless environments
that cannot host the database engine.

The package also provides a `@libsql/client` compatibility layer in the
`@tursodatabase/serverless/compat` module for drop-in replacement for
existing clients.

packages/turso-serverless/examples/remote/index.mjs

@@ -0,0 +1,36 @@
+import { connect } from "@tursodatabase/serverless";
+
+const client = connect({
+    url: process.env.TURSO_DATABASE_URL,
+    authToken: process.env.TURSO_AUTH_TOKEN,
+});
+
+await client.batch(
+    [
+        "CREATE TABLE IF NOT EXISTS users (email TEXT)",
+        "INSERT INTO users VALUES ('first@example.com')",
+        "INSERT INTO users VALUES ('second@example.com')",
+        "INSERT INTO users VALUES ('third@example.com')",
+    ],
+    "write",
+);
+
+// Using execute method
+const result = await client.execute("SELECT * FROM users");
+console.log("Users (execute):", result.rows);
+
+// Using prepare and get method
+const stmt = client.prepare("SELECT * FROM users LIMIT 1");
+const firstUser = await stmt.get();
+console.log("First user:", firstUser);
+
+// Using prepare and all method
+const allUsers = await stmt.all();
+console.log("All users (all):", allUsers);
+
+// Using prepare and iterate method
+console.log("Users (iterate):");
+const iterateStmt = client.prepare("SELECT * FROM users");
+for await (const user of iterateStmt.iterate()) {
+    console.log("  -", user[0]);
+}