made this: if Tray become disabled and startInTray was enabled, startInTray before blocks, goes disabled too

move error_matrixid label below matrixid input, made hide/show for the label, made red underline for invalid input, add to TextField class isValid() setValid() for custom validation

Added QLabel for matrixIdError output and added new function which output input id error, improve code like suggest @deepbluev7, return for error_label setWordWrap

There is no need to iterate over a list, flags can be applied and stored
simultaneously.

¯\_(ツ)_/¯ IDK, I like to write something after, sometimes

Allow sending:

¯\_(ツ)_/¯ some text

By entering:

/shrug some text

It's supported in Element. If you did it in nheko, you just used to lose the
extra text.

Not putting text is still supported, a ternary operator makes sure a
space is only inserted if the text isn't empty, to avoid having a trailing
space.

This is for consistency with "Start a private chat", and is more
specific.

This is less ambiguous. Moreover, this mode might be useful on a
computer touchscreen.

This is less ambiguous, as it aligns with the other uses.

Trusted might refer to something else, like the reputation project.
You can trust a user you haven't verified.

Also mention devices as this shares keys with verified devices, for when device
verification was performed without cross-signing.