Include static files in package distribution

- Add static dir to MANIFEST.in
- Update package data config
- Ensure static assets are bundled
- Fix missing static file issue

(cherry picked from commit 16d3d82a0e)

MANIFEST.in

@@ -1,3 +1,4 @@
 include requirements.txt
 include lightrag/api/requirements.txt
 recursive-include lightrag/api/webui *
+recursive-include lightrag/api/static *

pyproject.toml

@@ -136,7 +136,7 @@ include-package-data = true
 version = {attr = "lightrag.__version__"}
 
 [tool.setuptools.package-data]
-lightrag = ["api/webui/**/*"]
+lightrag = ["api/webui/**/*", "api/static/**/*"]
 
 [tool.ruff]
 target-version = "py310"