replace: swap prosappweb content for prosapp_web_app (more complete version)

prosapp_web_app has chat, dashboard, calendar, support, 13 providers and
Fluro URL routing. Keep Dockerfile + nginx.conf from previous prosappweb.
Upgrade google_fonts 6.2.1 → 8.1.0 (Dart 3.12 compat fix).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

windows/flutter/CMakeLists.txt

@@ -10,6 +10,11 @@ include(${EPHEMERAL_DIR}/generated_config.cmake)
 # https://github.com/flutter/flutter/issues/57146.
 set(WRAPPER_ROOT "${EPHEMERAL_DIR}/cpp_client_wrapper")
 
+# Set fallback configurations for older versions of the flutter tool.
+if (NOT DEFINED FLUTTER_TARGET_PLATFORM)
+  set(FLUTTER_TARGET_PLATFORM "windows-x64")
+endif()
+
 # === Flutter Library ===
 set(FLUTTER_LIBRARY "${EPHEMERAL_DIR}/flutter_windows.dll")
 
@@ -92,7 +97,7 @@ add_custom_command(
   COMMAND ${CMAKE_COMMAND} -E env
     ${FLUTTER_TOOL_ENVIRONMENT}
     "${FLUTTER_ROOT}/packages/flutter_tools/bin/tool_backend.bat"
-      windows-x64 $<CONFIG>
+      ${FLUTTER_TARGET_PLATFORM} $<CONFIG>
   VERBATIM
 )
 add_custom_target(flutter_assemble DEPENDS