[WIP] add dynamic-hotkeys functionality

[rexagod]

Fixes #376

cc @sashadev-sky @jywarren

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[sashadev-sky]

@rexagod very smart implementation!!! Thank you, i'm going to rebase this and then check if this can easily be applied to the collection group too. If it can, I will push that and merge this! If it can't, your call if you want to work on that here or merge and do it in a new PR. Either way will bump the version before merge.

[sashadev-sky]

@rexagod I did a bad job at rebasing your code formatting PR, so I am going to merge this because it address some of the updates I overrwrote.

The only part left to resolve is how to make this work for the collection group. If you have one image that has scale in its toolbar, for ex, but another that doesnt, how do you make scale available on only one of them?