chore(repo): replace app symlink/submodule with in-repo app directory; enable committing app/Dockerfile and tooling\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

app/.dockerignore

@@ -0,0 +1,12 @@
+.git
+.gitignore
+__pycache__/
+*.pyc
+*.pyo
+*.pyd
+.venv/
+venv/
+build/
+dist/
+node_modules/
+.cache/