fix(common): change runtime path

Author: nickchecan

bin/compile

@@ -133,13 +133,15 @@ if [ -f "pyproject.toml" ] && [ -f "uv.lock" ]; then
   # project itself is not installed by the exported third-party requirements.
   if [ -d "$SRC_DIR" ]; then
     cat > "$PROFILE_DIR/python.sh" <<EOF
-export PATH="$PYTHON_SHIM_DIR:$PACKAGE_BIN_DIR:\${PATH}"
-export PYTHONPATH="$SRC_DIR:$SITE_PACKAGES_DIR:\${PYTHONPATH}"
+export APP_DIR="\${HOME}/app"
+export PATH="\$APP_DIR/.python/bin:\$APP_DIR/.python_packages/bin:\${PATH}"
+export PYTHONPATH="\$APP_DIR/src:\$APP_DIR/.python_packages/lib/python${PYTHON_VERSION}/site-packages:\${PYTHONPATH}"
 EOF
   else
     cat > "$PROFILE_DIR/python.sh" <<EOF
-export PATH="$PYTHON_SHIM_DIR:$PACKAGE_BIN_DIR:\${PATH}"
-export PYTHONPATH="$SITE_PACKAGES_DIR:\${PYTHONPATH}"
+export APP_DIR="\${HOME}/app"
+export PATH="\$APP_DIR/.python/bin:\$APP_DIR/.python_packages/bin:\${PATH}"
+export PYTHONPATH="\$APP_DIR/.python_packages/lib/python${PYTHON_VERSION}/site-packages:\${PYTHONPATH}"
 EOF
   fi
 else

test/unit/compile_test.sh

@@ -216,9 +216,9 @@ test_compile_succeeds_for_locked_uv_project() {
   assert_path_exists "$export_file" "compile should write the exported requirements file"
   assert_path_exists "$shim_dir/python3" "compile should create a python3 shim for runtime commands"
   assert_path_exists "$shim_dir/python" "compile should create a python shim for runtime commands"
-  assert_file_contains "$profile_file" "$site_packages_dir" "profile script should add staged dependencies to PYTHONPATH"
-  assert_file_contains "$profile_file" "$shim_dir" "profile script should add the managed Python shims to PATH"
-  assert_file_contains "$profile_file" "$package_bin_dir" "profile script should add staged console scripts to PATH"
+  assert_file_contains "$profile_file" 'export APP_DIR="${HOME}/app"' "profile script should resolve paths from the droplet app directory at runtime"
+  assert_file_contains "$profile_file" '$APP_DIR/.python/bin:$APP_DIR/.python_packages/bin:${PATH}' "profile script should add the managed Python shims and staged console scripts to PATH"
+  assert_file_contains "$profile_file" '$APP_DIR/.python_packages/lib/python3.13/site-packages:${PYTHONPATH}' "profile script should add staged dependencies to PYTHONPATH"
   assert_file_contains "$TEST_ROOT/uv.log" "python install 3.13" "compile should install the Python version pinned by .python-version"
   assert_file_contains "$TEST_ROOT/uv.log" "python find --managed-python 3.13" "compile should resolve the managed interpreter path after installation"
   assert_file_contains "$TEST_ROOT/uv.log" "export --locked --format requirements-txt --no-emit-local -o $export_file" "compile should export locked third-party dependencies"
@@ -242,7 +242,7 @@ test_compile_adds_src_directory_to_pythonpath_when_present() {
 
   # Assert
   assert_exit_code "$status" 0 "compile should succeed for src-layout projects"
-  assert_file_contains "$profile_file" "$build_dir/src" "profile script should add src layout projects to PYTHONPATH"
+  assert_file_contains "$profile_file" '$APP_DIR/src:$APP_DIR/.python_packages/lib/python3.13/site-packages:${PYTHONPATH}' "profile script should add src layout projects to PYTHONPATH using runtime paths"
 }
 
 test_compile_accepts_two_argument_cf_invocation() {