Follow-up from "Use constant color aliases for deprecated color values"

The following discussions from !5906 (merged) should be addressed:

@danmh started a discussion:
suggestion (non-blocking): off by one
```
        "dark": "{color.purple.600}"
```
@danmh started a discussion:
suggestion (non-blocking): off by one
```
        "dark": "{color.purple.700}"
```
@danmh started a discussion:
suggestion (non-blocking): off by one
```
        "dark": "{color.purple.800}"
```
@danmh started a discussion:
suggestion (non-blocking): off by one
```
        "dark": "{color.purple.900}"
```
@danmh started a discussion:
suggestion (non-blocking): off by one
```
        "dark": "{color.purple.950}"
```