fix: Handle multiple spaces in Raw Data line for BMG MARS parser (#1243)

## Summary
BMG PHERAstar CSV exports can write the `Raw Data` header with more than
one space before the filter parenthesis (e.g. `Raw Data (450)` with two
spaces). The parser's regexes required exactly one literal space, so
parsing failed with:

```
AllotropeConversionError: Raw Data line not found in input file.
```

This relaxes the whitespace to `\s+` in the search regex and all four
`FILTER_FORMATS` patterns in `bmg_mars_structure.py`.

## Changes
- `bmg_mars_structure.py`: `Raw Data \(` → `Raw Data\s+\(` in the search
regex and all filter format patterns.
- Added regression test data: `PHERAstar output file.CSV` (a real
double-space export) and its generated expected `.json`.

## Testing
- All 8 `bmg_mars` tests pass.
- `hatch run lint` (ruff, black, mypy) clean.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: nathan-stender

src/allotropy/parsers/bmg_mars/bmg_mars_structure.py

@@ -71,19 +71,19 @@ class Header:
 
     FILTER_FORMATS: ClassVar[dict[str, tuple[str, FilterHandler]]] = {
         "Raw Data (Ex/Em)": (
-            r"Raw Data \((\d+\.?\d*)/(\d+\.?\d*)\)",
+            r"Raw Data\s+\((\d+\.?\d*)/(\d+\.?\d*)\)",
             lambda m: (float(m.group(2)), float(m.group(1))),
         ),
         "Raw Data (Ex Em)": (
-            r"Raw Data \((\d+\.?\d*) (\d+\.?\d*)\)",
+            r"Raw Data\s+\((\d+\.?\d*) (\d+\.?\d*)\)",
             lambda m: (float(m.group(2)), float(m.group(1))),
         ),
         "Raw Data (Em)": (
-            r"Raw Data \((\d+\.?\d*)\)",
+            r"Raw Data\s+\((\d+\.?\d*)\)",
             lambda m: (float(m.group(1)), None),
         ),
         "Raw Data (No filter)": (
-            r"Raw Data \(No filter\)",
+            r"Raw Data\s+\(No filter\)",
             lambda _: (None, None),
         ),
     }
@@ -100,7 +100,7 @@ def create(data: SeriesData, header_content: str) -> Header:
 
         # Get wavelengths from RawData line
         raw_data_line = assert_not_none(
-            re.search(r"Raw Data \(.*?\)", header_content),
+            re.search(r"Raw Data\s+\(.*?\)", header_content),
             msg="Raw Data line not found in input file.",
         ).group(0)
 

tests/parsers/bmg_mars/testdata/PHERAstar output file.CSV

@@ -0,0 +1,18 @@
+User: USER,Path: C:\Program Files (x86)\BMG\PHERAstar\User\Data,Test run no.: 65
+Test name: dsRNA ELISA,Date: 6/18/2026,Time: 3:56:48 PM
+
+ID1: 20260618 dsRNA _PLATE_01_18Jun26,
+Absorbance
+
+Raw Data  (450)
+
+,1,2,3,4,5,6,7,8,9,10,11,12,
+A,1.691,1.557,1.583,0.596,0.336,0.221,0.162,0.091,0.098,0.086,0.213,1.641
+B,1.016,0.986,0.953,0.479,0.321,0.199,0.135,0.094,0.1,0.087,0.126,1.194
+C,0.561,0.503,0.503,0.07,0.082,0.078,0.084,0.094,0.101,0.08,0.13,1.637
+D,0.342,0.272,0.28,0.072,0.083,0.165,0.181,0.074,0.091,0.076,0.094,1.171
+E,0.184,0.16,0.165,0.069,0.07,0.142,0.078,0.079,0.089,0.081,0.098,1.361
+F,0.119,0.113,0.122,0.076,0.074,0.082,0.08,0.084,0.096,0.083,0.091,0.914
+G,0.086,0.093,0.097,0.098,0.073,0.086,0.086,0.086,0.087,0.085,0.094,1.4
+H,0.069,0.076,0.074,0.074,0.077,0.091,0.086,0.096,0.094,0.087,0.088,0.884
+