chore: Update structure mappings to correct missing icons

[johncowen]

Note: I wasn't quite sure who to add as reviewer, please feel free to add any other relevant folks!

:pushpin: Summary

Updates the structure-mappings file to correct missing icons

:hammer_and_wrench: Detailed Description

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:camera_flash: Screenshots

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:link: External Links

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[didoo]

@heatherlarsen @cveigt assigned to you for review (and removed me and Hector, it's just a matter of checking the mapping).

[johncowen]

K those extra ones are there @heatherlarsen whenever you get a sec, FYI I'm not blocked by this so no rush

[johncowen]

Hey @heatherlarsen

I popped another commit on the end of here (sorry I know some folks prefer adding commits, and some prefer new PRs but figured for this new PR would be overkill)

@jnwright noticed that the mapping here for Structure's triangle (which by default is filled) is wrong as it points to Flights outlined variant. The triangle in the following image should be filled:

I updated the mapping and checked it locally:

I also noticed that the circle one here is probably wrong also, and I'm guessing there are possibly a few more, do you want me to just keep pushing on the end of here, or shall I make new PRs when we spot them?

ty!

[heatherlarsen]

@johncowen adding more fixes here is ok with me, if you find them.

[Dhaulagiri]

I'm going to bring this in as-is for now. If there are additional changes feel free to send them along.