OPTIM: Speeding up EOReader

It could be really useful to use external libraries to speed up EOReader and ensure the clusterization works properly:

[ ] Optimize the code using libraries such as numba, xarray-geospatial...
[x] Use WarpedVRT instead of reprojecting data (VHR...)
[ ] Use directly S3 files when possible (wait for cloudpathlib to work properly with fsspec or maybe use universal_pathlib) (-> small optim, most of the time S3 files are used, with the Path converted to string -> but better for the code's reading)
[ ] Hope that one day SNAP will be able to process S3-stored products (right now, it seems still impossible)
[ ] Make Dask really work (even if #4 is closed)
- Ensure reading and writing is accelerated
- Ensure everything is as lazy as possible (don't call .data !)
- Ensure that everything has proper chunks
- Check if reprojection, geocoding, index computation can be daskified and/or optimized:
  - [x] Spyndex #47
  - [x] geocode S3 #55,
  - [ ] reprojection: #115
  - [x] Don't load data into memory before computing spectral indices
  - [x] Use chunks when reading data
[x] Enforce the window reading (#25)
[ ] Don't use SNAP for SAR data (#2)

sertit / eoreader