Replace `Image2DCollection` with `MultiscaleImage` in Python and C++

[jp-dark]

This PR cleans up the multiscale image pyramid class. It includes the following:

• [x] Merge ImageCollection and Image2DCollection into a single class
• [x] Rename new class to MultiscaleImage
• [x] Remove Collection methods from MultiscaleImage (e.g. ability to add subcollections, sparse arrays, etc.)
• [x] Add checking that all images have the same number of channels
• [x] Add checks for number of dimensions (NotImplemented for more than 2 spatial dimensions + 1 channel dimension for now)
• [x] Add method to get transformations from image levels
• [x] Update image name in experimental Visium ingestor

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 57.48299% with 125 lines in your changes missing coverage. Please review.

Project coverage is 80.08%. Comparing base (6fb2894) to head (0ec09bf). Report is 2 commits behind head on spatial.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## spatial #2946 +/- ## =========================================== + Coverage 80.05% 80.08% +0.02% =========================================== Files 45 46 +1 Lines 4719 4755 +36 =========================================== + Hits 3778 3808 +30 - Misses 941 947 +6 ``` | [Flag](https://app.codecov.io/gh/single-cell-data/TileDB-SOMA/pull/2946/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data) | Coverage Δ | | |---|---|---| | [python](https://app.codecov.io/gh/single-cell-data/TileDB-SOMA/pull/2946/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data) | `80.08% <57.48%> (+0.02%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/single-cell-data/TileDB-SOMA/pull/2946/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data) | Coverage Δ | | |---|---|---| | [python_api](https://app.codecov.io/gh/single-cell-data/TileDB-SOMA/pull/2946/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data) | `80.08% <57.48%> (+0.02%)` | :arrow_up: | | [libtiledbsoma](https://app.codecov.io/gh/single-cell-data/TileDB-SOMA/pull/2946/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=single-cell-data) | `∅ <ø> (∅)` | |