Reorder legends

[user202729]

The current legend content is like

Boxes:
    definitions
Ellipses:
    theorems and lemmas
Blue border:
    the statement of this result is ready to be formalized; all prerequisites are done
Orange border:
    the statement of this result is not ready to be formalized; the blueprint needs more work
Blue background:
    the proof of this result is ready to be formalized; all prerequisites are done
Green border:
    the statement of this result is formalized
Green background:
    the proof of this result is formalized
Dark green background:
    the proof of this result and all its ancestors are formalized
Dark green border:
    this is in Mathlib

I find the ordering very confusing.

The new ordering is such that it lists all border entries before the background entries, and in order of increasing completion.

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Actually I prefer something like this

Boxes:
    definitions
Ellipses:
    theorems and lemmas
Border:
    Orange:
        the statement of this result is not ready to be formalized; the blueprint needs more work
    Blue:
        the statement of this result is ready to be formalized; all prerequisites are done
    Green:
        the statement of this result is formalized
    Dark green:
        this is in Mathlib
Background:
    Blue:
        the proof of this result is ready to be formalized; all prerequisites are done
    Green:
        the proof of this result is formalized
    Dark green:
        the proof of this result and all its ancestors are formalized

but that appears to require a little more work to implement the three-level hierarchy.