Add native self-hosted instance connection to fluxer_desktop

Trimmed monorepo checkout (fluxer_desktop + packages/voice_engine_v2 +
tools/ci) with a "Connect to a Different Server" menu item and popout
that lets the desktop app switch to any self-hosted Fluxer instance,
plus fixes for well-known discovery on single-domain self-hosted
deployments and a false-positive ERR_ABORTED on same-origin client
redirects during the switch. Defaults to chat.fluxr.chat and uses an
isolated userData directory from the official build.

fluxer_desktop/native/platform-info/test/loader.test.mjs

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import platformInfo from '../index.js';
+
+test('loader exposes a stable optional native surface', () => {
+	assert.equal(typeof platformInfo, 'object');
+	assert.equal(platformInfo.getGpuInfo === null || typeof platformInfo.getGpuInfo === 'function', true);
+	assert.equal(platformInfo.loadError === null || platformInfo.loadError instanceof Error, true);
+});
+
+test('loader resolves native binaries for supported platforms and architectures', () => {
+	assert.equal(platformInfo._private.nativeFileName('darwin', 'x64'), 'platform-info.darwin-x64.node');
+	assert.equal(platformInfo._private.nativeFileName('darwin', 'arm64'), 'platform-info.darwin-arm64.node');
+	assert.equal(platformInfo._private.nativeFileName('linux', 'x64'), 'platform-info.linux-x64-gnu.node');
+	assert.equal(platformInfo._private.nativeFileName('linux', 'arm64'), 'platform-info.linux-arm64-gnu.node');
+	assert.equal(platformInfo._private.nativeFileName('win32', 'x64'), 'platform-info.win32-x64-msvc.node');
+	assert.equal(platformInfo._private.nativeFileName('win32', 'arm64'), 'platform-info.win32-arm64-msvc.node');
+});