🎨 Palette: Add tooltips to input bar buttons

[kevinaboos]

Added tooltips to 'Share location', 'Send message', and 'Cancel reply' buttons in RoomInputBar. The 'Send message' tooltip dynamically updates to 'Type a message to send' when the input is empty. This improves accessibility and usability by clarifying icon-only buttons.

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PR created automatically by Jules for task 11641960593845166221 started by @kevinaboos

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