SVG importer ignores `fill-rule="evenodd"`

## Description

The SVG importer does not respect `fill-rule="evenodd"`. A compound path whose inner subpath should create a transparent hole is imported as a solid shape. follow up of #4329

## Steps to reproduce

1. Open `fill-rule-evenodd.svg` in a browser or another SVG viewer. It appears as a purple square with a transparent square hole.
2. Import the same file into Graphite.
3. Compare the imported result with the browser rendering.

## Expected behavior

The imported shape is a purple square with a transparent square hole, matching the SVG rendering in a browser.

## Actual behavior

The inner square is filled, so the imported result is a solid purple square. The importer behaves as if the path used the default nonzero fill rule.

Start by locating the SVG importer and reproduce the issue with `fill-rule-evenodd.svg`, comparing Graphite's result with a browser or another SVG viewer. Trace how the importer handles `fill-rule="evenodd"`; done means the inner square becomes a transparent hole and the imported shape matches the SVG rendering.

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