feat: add zarr store

[cauriol]

This PR improves the way Zarr stores are exposed and accessed through the /data endpoint, allowing Zarr data to be accessed in a cloud-native way.

• Zarr store exposure via HTTP filesystem:
  The endpoint /data/{federation_backend}/{collection_id}/{item_id}/zarr exposes the Zarr store as an HTTP filesystem, follows the standard Zarr + fsspec access pattern. Clients can access the data remotely using common libraries such as zarr, xarray, or dask without downloading the full store.
  Exemple usage:

# pip install requests xarray zarr fsspec requests aiohttp dask
import xarray as xr

ds = xr.open_zarr(
    "https://<api-url>/data/<backend>/<collection>/<item>/{asset_name}.zarr",
    engine="zarr",
    chunks={},  
    decode_times=False,
    storage_options={
        "client_kwargs": {"trust_env": False},
    }
)

print(ds)

• Human-readable index:
  A dedicated endpoint: /data/{federation_backend}/{collection_id}/{item_id}/zarr/index returns a JSON listing of the files contained in the Zarr store and their paths.

• File access inside the Zarr store:
  Individual files can be accessed via: /data/{federation_backend}/{collection_id}/{item_id}/zarr/{path_to_file}, where path_to_file can be found in the human-readable index.

[github-actions]

Test Results

  2 files   -   2    2 suites   - 2   24s ⏱️ -32s
114 tests +  3  113 ✅ +  2  0 💤 ±0  1 ❌ +1 
228 runs   - 216  226 ✅  - 218  0 💤 ±0  2 ❌ +2 

For more details on these failures, see this check.

Results for commit d74acfb. ± Comparison against base commit b73a3b0.

♻️ This comment has been updated with latest results.

[github-actions]

Code Coverage

Details

Filename                                 Stmts    Miss  Cover    Missing
-------------------------------------  -------  ------  -------  ------------------------------------------------------------------------------------------------------------------------
eodag/__init__.py                            0       0  100.00%
eodag/app.py                                75      15  80.00%   153, 167-174, 185-187, 243-255, 259
eodag/client.py                             25       0  100.00%
eodag/config.py                             19       0  100.00%
eodag/constants.py                           5       0  100.00%
eodag/core.py                              309      27  91.26%   135-136, 146, 290-291, 381, 509-510, 529, 560, 646, 662-666, 680-684, 686-690, 695, 708, 718-720, 723-724, 734, 737, 753
eodag/cql_evaluate.py                       48      18  62.50%   48, 53, 58, 75, 78, 81, 86-99, 105
eodag/dag.py                                57       0  100.00%
eodag/errors.py                             94      12  87.23%   143, 160-163, 179, 202-212
eodag/logs.py                               62       9  85.48%   40-49, 105
eodag/middlewares.py                        32       2  93.75%   20, 24
eodag/telemetry.py                          44       0  100.00%
eodag/utils.py                              41      10  75.61%   44, 69, 72-73, 86, 90-98, 134
eodag/eodag_types/__init__.py                0       0  100.00%
eodag/eodag_types/queryables.py             42       8  80.95%   46, 50-51, 61, 77-81
eodag/eodag_types/search.py                 25      25  0.00%    20-69
eodag/extensions/collection_order.py        73       1  98.63%   106
eodag/extensions/data_download.py          147      46  68.71%   67-70, 80-92, 113, 144-145, 152, 167-174, 178-180, 183-184, 191-223, 235
eodag/extensions/ecmwf.py                   69       0  100.00%
eodag/extensions/filter.py                  96       9  90.62%   182-183, 275-276, 296, 304, 310, 328-330
eodag/extensions/offset_pagination.py       12       0  100.00%
eodag/extensions/stac.py                   167       3  98.20%   348-350
eodag/models/__init__.py                     0       0  100.00%
eodag/models/item.py                        85       6  92.94%   50-53, 55, 69
eodag/models/links.py                      147      13  91.16%   39, 93-95, 201, 219, 251, 298, 347-358
eodag/models/stac_metadata.py              104       6  94.23%   82, 150, 163-170
TOTAL                                     1778     210  88.19%

Diff against main

Filename                             Stmts    Miss  Cover
---------------------------------  -------  ------  -------
eodag/extensions/data_download.py      +26      +4  +3.42%
TOTAL                                  +26      +4  -0.05%

Results for commit: d74acfb

Minimum allowed coverage is 70%

♻️ This comment has been updated with latest results

[cauriol]

Currently, we only have DanubeHis and no other provider supporting Zarr, so it is difficult to properly test this part.

I will continue once we add another provider that supports Zarr.

The Zarr endpoint still needs to be implemented, along with the related tests.

[alambare]

I do not understand why fsspec, aiohttp and requests dependencies are needed here.
All the logic must be handled by EODAG. stac-fastapi-eodag is only a wrapper to expose EODAG as a webserver.