FEAT: Basic datasets feature

[codingl2k1]

What do these changes do?

• [ ] plugin merge chunks impl. hard code for merging datasets in this PR.
  • [ ] set initial_same_color_num = 1, related issue: https://github.com/xorbitsai/xorbits/issues/384
• [x] spread loader op among nodes.
  • [ ] stable bind band to op for cache reuse.
• [x] handle datasets without data files.
  • [ ] try download parquets if not data files.
• [x] impl to_dataframe().
  • [x] fill dtypes and shape from builder info if possible.
• [ ] use iterative tiling to parallel map arrow files or arrow record batches.
• [x] auto execute adapter.
• [x] add ut.
• [ ] add doc.
• [x] refine code and comments.

Known issue:

• fetch data from worker node may be failed because the datasets could be a file mapping.
• rechunk is not fully supported.

Related issue number

Fixes #xxxx

Check code requirements

• [ ] tests added / passed (if needed)
• [ ] Ensure all linting tests pass

[codecov[bot]]

Codecov Report

Merging #600 (747a4ff) into main (d4092fa) will increase coverage by 0.10%. The diff coverage is 97.94%.

@@            Coverage Diff             @@
##             main     #600      +/-   ##
==========================================
+ Coverage   93.53%   93.64%   +0.10%     
==========================================
  Files        1012     1020       +8     
  Lines       78737    79029     +292     
  Branches    16358    16392      +34     
==========================================
+ Hits        73647    74006     +359     
+ Misses       3427     3363      -64     
+ Partials     1663     1660       -3     

Flag	Coverage Δ
unittests	93.53% <97.60%> (+0.10%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
python/xorbits/core/data.py	99.11% <50.00%> (-0.89%)	:arrow_down:
...n/xorbits/datasets/backends/huggingface/rechunk.py	93.75% <93.75%> (ø)
...bits/datasets/backends/huggingface/to_dataframe.py	96.77% <96.77%> (ø)
python/xorbits/datasets/dataset.py	97.56% <97.56%> (ø)
python/xorbits/_mars/core/entity/output_types.py	84.48% <100.00%> (+0.27%)	:arrow_up:
python/xorbits/_mars/utils.py	89.64% <100.00%> (+0.04%)	:arrow_up:
python/xorbits/datasets/adapter.py	100.00% <100.00%> (ø)
...thon/xorbits/datasets/backends/huggingface/core.py	100.00% <100.00%> (ø)
...on/xorbits/datasets/backends/huggingface/loader.py	100.00% <100.00%> (ø)
...ython/xorbits/datasets/backends/huggingface/map.py	100.00% <100.00%> (ø)
... and 1 more

... and 13 files with indirect coverage changes