The README Quick Start tells users to `pip install wifi-densepose` and then
`from wifi_densepose import WiFiDensePose`, but no `wifi_densepose` Python
package existed — only `v1/src`. This adds a top-level `wifi_densepose/`
package with a WiFiDensePose facade class matching the documented API, and
updates pyproject.toml to include it in the distribution.
Closes#314
rUv