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/win-game-capture/inject-helper/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+name = "fluxer_inject_helper"
+version = "0.0.0"
+edition = "2024"
+license = "AGPL-3.0-or-later"
+publish = false
+
+[workspace]
+resolver = "2"
+
+[[bin]]
+name = "fluxer-inject-helper"
+path = "src/main.rs"
+
+[profile.release]
+# Keep the helper tiny: it is a one-shot injector exe shipped alongside the
+# hook DLLs, so optimise hard for size and strip symbols.
+opt-level = "z"
+lto = true
+codegen-units = 1
+panic = "abort"
+strip = true
+
+[target.'cfg(target_os = "windows")'.dependencies]
+windows-sys = {version = "0.61.2", features = [
+    "Win32_Foundation",
+    "Win32_Security",
+    "Win32_System_Diagnostics_Debug",
+    "Win32_System_LibraryLoader",
+    "Win32_System_Memory",
+    "Win32_System_Threading",
+]}