fix(amazonq): Correctly report suggestion state.

[leigaol]

Problem

Suggestion state reporting is incorrect.

Solution

1. When receiving a suggestion, if the cursor is behind invoking position, DISCARD suggestion
2. When receiving a suggestion, if the cursor is after invoking position and the typeahead does not match DISCARD suggestion.
3. When user does not do anything with a shown suggestion, we REJECT it the next time we invoke for new suggestions.

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[github-actions]

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