fix(amazonq): Faster and more responsive auto trigger UX.

[leigaol]

Problem

1. when intelliSense suggestion is surfaced, inline completion are not shown even if provideInlineCompletionItems have returned valid items.
2. provideInlineCompletionItems is unnecessarily debounced at 200ms which creates a user perceivable delay for inline completion UX. We already blocked concurrent API call.
3. The items returned by provideInlineCompletionItems, even though they match the typeahead of the user's current editor (they can be presented), sometimes VS Code decides to not show them to avoid interrupting user's typing flow. This not show suggestion decision is not emitted as API callback or events, causing us to report the suggestion as Rejected but it should be Discard.

Solution

1. Force the item to render by calling editor.action.inlineSuggest.trigger command.

3. Remove the debounce

4. Use a specific command with when clause context to detect if a suggestion is shown or not.

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
  • Confirm whether tests should be added or ensure the PR description explains why tests are not required.