fix: focus composition input when typing

[DonnaIsabel97]

First time contributor checklist:

• I have read the README and Contributor Guidelines

Contributor checklist:

• My commits are in nice logical chunks with good commit messages
• My changes are rebased on the latest dev branch
• A yarn ready run passes successfully (more about tests here)
• My changes are ready to be shipped to users

Description

What does this PR do?

Focuses the conversation composition input when the user starts typing a normal printable character outside the chatbar. The first typed character is preserved by using the existing composition input ref methods.

Why was this PR needed?

Typing while a conversation is open currently does nothing unless the user first clicks the chatbar or uses the existing focus shortcut. This makes composing messages feel finicky.

What are the relevant issue numbers?

Closes #460

Testing

• Manually verified typing a normal letter outside the chatbar focuses the chatbar.
• Manually verified the first typed character is inserted.
• Manually verified typing inside search/input fields does not move focus to the chatbar.
• Manually verified modifier-key shortcuts are ignored.