Incorrect function highlighting in raw format (rf) string

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I'm getting some incorrect highlighting inside an rf string, in particular for the `.` and `(1)` portions, as well as the curly braces. Take a look:

* **Editor name and version**: VSCode
* **Platform**: Windows
* **Color scheme**: Default
* **MagicPython version**: v1.1.0
* **A sreenshot**:
* **5-10 lines of surrounding code**:
```
for item in (
re.split(rf" ?\r
(?=\d+{match.group(1)})", text)
if (match := re.match(r"1( ?[-.])", text)) is not None
else [text]
):
```

Start by reproducing the supplied raw-format string in the supported editor and compare highlighting of the dot, `(1)`, and curly braces. Trace the syntax-highlighting behavior for this example; done means those portions are highlighted consistently with the surrounding Python expression.

Written by the indexing model from the issue text.