feat: add desktop packaging (pywebview + PyInstaller)

- resource_path.py: frozen/dev path resolution for bundled data files
- app_desktop.py: pywebview entry point (Dash in daemon thread)
- app.spec: PyInstaller onedir config with data files and hidden imports
- Updated queries.py, card_browser.py, app.py to use get_resource_path()
- Added pywebview + pyinstaller to project dependencies
- Fixed unresolved merge conflict in .gitignore
- Removed stale 01_nhs_classic.html and AdditionalAnalytics.md

pyproject.toml

@@ -13,6 +13,8 @@ dependencies = [
     "pillow>=10.0.0",
     "plotly>=5.15.0",
     "pyarrow>=20.0.0",
+    "pyinstaller>=6.18.0",
+    "pywebview>=6.1",
     "snowflake-connector-python>=3.0.0",
     "tomli>=2.0.0",
 ]