[FEATURE]:Accessibility mode for screen reader users

[destructatron]

Feature hasn't been suggested before.

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Describe the enhancement you want to request

At the moment, Opencode is actively hostile to any screen readers trying to use the TUI. Emojis, animations and unicode characters add extra noise the text to speech voice is reading to a blind user, which are only there for visual effects in the first place. An accessibility mode would remove those and replace them with more textual equivalents, for instance the spinner being changed to some text when the AI is working and not constantly updating, as this makes the screen reader's review focus jump to the bottom of the window or close to it every time a text update happens.