fix: use --no-cache in parallel yarn install fallback

Parallel yarn install commands (renderer + client) corrupt the shared
yarn cache, causing vite/pixi.js to be missing despite yarn install
succeeding. Add --no-cache to the final fallback install to force a
clean fetch from the registry.

update-Nitrov3.sh

@@ -1138,7 +1138,9 @@ update_renderer() {
         if [ ! -d node_modules/pixi.js ]; then
             warn "Renderer: node_modules incomplete — cleaning and doing full install"
             clean_node_modules
-            yarn install >> "$LOG_FILE" 2>&1 || { spinner_stop fail; die "yarn install failed (see: %s)" "$LOG_FILE"; }
+            # Parallel yarn installs (renderer + client) can corrupt the shared
+            # yarn cache, so force a clean fetch with --no-cache as a last resort.
+            yarn install --no-cache >> "$LOG_FILE" 2>&1 || { spinner_stop fail; die "yarn install failed (see: %s)" "$LOG_FILE"; }
         fi
         spinner_stop ok; ok "Renderer dependencies installed"
     else
@@ -1166,7 +1168,9 @@ update_client() {
         if [ ! -x node_modules/.bin/vite ]; then
             warn "Nitro-V3: vite missing after install — cleaning node_modules and doing full install"
             clean_node_modules
-            yarn install >> "$LOG_FILE" 2>&1 || { spinner_stop fail; die "yarn install failed (see: %s)" "$LOG_FILE"; }
+            # Parallel yarn installs (renderer + client) can corrupt the shared
+            # yarn cache, so force a clean fetch with --no-cache as a last resort.
+            yarn install --no-cache >> "$LOG_FILE" 2>&1 || { spinner_stop fail; die "yarn install failed (see: %s)" "$LOG_FILE"; }
         fi
         spinner_stop ok
         spinner_start "Building frontend..."