feat: add Cleanflix Connector Tauri desktop app

Move the Mac Tauri UI (pro.cleanflix.connector) into this repo under desktop/. Bundled Node runtime stays gitignored; package scripts fetch it when building.

desktop/scripts/prepare-sidecar.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env sh
+set -eu
+ROOT=$(CDPATH= cd -- "$(dirname -- "$0")/../.." && pwd)
+OUT="$ROOT/desktop/sidecar"
+NODE_VERSION=${NODE_VERSION:-22.14.0}
+rm -rf "$OUT"
+mkdir -p "$OUT"
+cp "$ROOT/server.js" "$ROOT/library.js" "$ROOT/hash-password.js" "$ROOT/package.json" "$OUT/"
+cp -R "$ROOT/distribution/common" "$OUT/distribution-common"
+case "$(uname -s)-$(uname -m)" in
+  Darwin-arm64) ARCHIVE="node-v$NODE_VERSION-darwin-arm64" ;;
+  Darwin-x86_64) ARCHIVE="node-v$NODE_VERSION-darwin-x64" ;;
+  Linux-x86_64) ARCHIVE="node-v$NODE_VERSION-linux-x64" ;;
+  *) echo "Unsupported build platform" >&2; exit 1 ;;
+esac
+curl -fsSL "https://nodejs.org/dist/v$NODE_VERSION/$ARCHIVE.tar.gz" | tar -xz -C "$OUT"
+mv "$OUT/$ARCHIVE" "$OUT/node"
+"$OUT/node/bin/npm" install --omit=dev --prefix "$OUT"