feat: make Map implement MutableMapping interface

[tlambert03]

closes #248 ... This PR makes ome_types.model.Map behave like a proper mutable mapping. so, it's much easier to cast to/from a dict object:

after this PR, you can do:

import ome_types
from ome_types.model import MapAnnotation

ome_test = ome_types.OME()

data = {
    "uiWidth": 1608,
    "uiWidthBytes": 3216,
    "uiHeight": "1608",
    "uiComp": "1",
}

ome_test.structured_annotations.extend([MapAnnotation(value=data)])
print(ome_test.model_dump(exclude_defaults=True))
print(ome_test.to_xml())

prints:

{
    "structured_annotations": {
        "map_annotations": [
            {
                "id": "Annotation:0",
                "value": {
                    "uiWidth": "1608",
                    "uiWidthBytes": "3216",
                    "uiHeight": "1608",
                    "uiComp": "1",
                },
                "kind": "mapannotation",
            }
        ]
    }
}

and

<OME xmlns="http://www.openmicroscopy.org/Schemas/OME/2016-06" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.openmicroscopy.org/Schemas/OME/2016-06 http://www.openmicroscopy.org/Schemas/OME/2016-06/ome.xsd">
  <StructuredAnnotations>
    <MapAnnotation ID="Annotation:0">
      <Value>
        <M K="uiWidth">1608</M>
        <M K="uiWidthBytes">3216</M>
        <M K="uiHeight">1608</M>
        <M K="uiComp">1</M>
      </Value>
    </MapAnnotation>
  </StructuredAnnotations>
</OME>

also note that you would be able to use standard dict-like methods to modify the Map object (like __getitem__, __setitem__, .get(), etc...)

[codecov]

Codecov Report

Attention: Patch coverage is 88.37209% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 86.72%. Comparing base (80d6a40) to head (6651747).

Files	Patch %	Lines
src/ome_types/_mixins/_map_mixin.py	90.00%	3 Missing ⚠️
src/ome_types/_mixins/_base_type.py	75.00%	1 Missing ⚠️
src/ome_types/_mixins/_validators.py	85.71%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #249      +/-   ##
==========================================
+ Coverage   86.66%   86.72%   +0.05%     
==========================================
  Files          24       25       +1     
  Lines        1200     1243      +43     
==========================================
+ Hits         1040     1078      +38     
- Misses        160      165       +5     

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[codspeed-hq]

CodSpeed Performance Report

Merging #249 will not alter performance

_{Comparing better-map (6651747) with main (80d6a40)}

Summary

✅ 9 untouched benchmarks

[tlambert03]

cc @phisanti, how's this look to you?

I could also add this to ND2.ome_metadata as a full=True option to store all the metadata we can find

[phisanti]

Adding all the OME metadata directly in the nd2 would be very useful, save me one function in the code.