Better Key Binding to Write Amharic

Microsoft's Amharic IME documentation (https://learn.microsoft.com/en-us/globalization/input/amharic-ime) uses a
straightforward phoneme-to-character transliteration scheme (e.g. `k` → ክ, `re` → ረ, `m` → ም, `t` → ት) and could be
used as a reference point for filling gaps — particularly for characters that don't currently map to any input sequence.
Open to using a different established scheme instead, as long as it accounts for every Amharic character consistently
It's the most common and widely used binding system so using it better.

Start by locating the current Amharic key-binding implementation and compare its supported input sequences with the Microsoft Amharic IME documentation linked in the issue. Define the completed work as a consistent transliteration scheme that provides an input sequence for every Amharic character, then verify the affected input behavior in the web platform.

Written by the indexing model from the issue text.