After the removal of the "normal" attribute providers, we no longer
use the concept of read-only attributes. Removing this status simplifies
code, clarifies the design, and removes potentially buggy corner cases.
Pull Request #104795
The "normal" was added before fields existed because we needed a
way to expose the data to geometry nodes. It isn't really an attribute,
because it's read-only and it's derived rather than original data.
No features have relied on the "normal" attribute existing, except
for the corresponding column in the spreadsheet. However, the
column in the spreadsheet is also inconsistent, since it isn't an
attribute but looks just like the other columns. The normal is
always visible in the spreadsheet.
Pull Request #104795
Hans Goudey