Add Docker image and compose for Needle web exports

Serve production Vite dist with nginx; optional SampleScene profile.

Made-with: Cursor

.dockerignore

@@ -0,0 +1,25 @@
+# Git / IDE
+.git
+.gitignore
+**/.cursor
+**/.vs
+.idea
+
+# Unity (not needed to build Needle web bundle)
+Library/
+Temp/
+Logs/
+UserSettings/
+MemoryCaptures/
+Recordings/
+obj/
+
+# Host-side Node (reinstalled in container)
+**/node_modules/
+
+# Build output (rebuilt in container)
+**/Needle/*/dist/
+
+# OS
+.DS_Store
+Thumbs.db