fix(compiler): preserve native boolean semantics in page branches

packages/compiler/test/conditional-boolean-attributes.test.ts

@@ -0,0 +1,23 @@
+import { expect, test } from "bun:test";
+import { parse, generate } from "../src/index.ts";
+
+test("native boolean attributes inside conditional and loop bodies use presence semantics", async () => {
+  const source = `page Example {
+    load server account { return {} }
+    view {
+      {#if account.visible}<input required disabled="{!account.edit}" />{/if}
+      {#each account.rows as row}<input type="checkbox" checked="{row.checked}" disabled="false" />{/each}
+    }
+  }`;
+  const code = new Bun.Transpiler({ loader: "ts" }).transformSync(generate(parse(source)));
+  const mod = await import("data:text/javascript;base64," + Buffer.from(code).toString("base64"));
+  const html = await mod.default({
+    account: { visible: true, edit: true, rows: [{ checked: false }, { checked: true }] },
+  });
+  expect(html).not.toContain("disabled");
+  expect(html).not.toContain('checked="false"');
+  expect(html.match(/ checked/g)).toHaveLength(1);
+  expect(html).toContain("required");
+  const denied = await mod.default({ account: { visible: true, edit: false, rows: [] } });
+  expect(denied).toContain(" disabled");
+});