Adds command listeners for undo

[dingfeli]

Issue #, if available:
Auto trigger is done via a document listener.
Inline preview makes some assumptions about the editor state, such as caret offset. Changes made to the document via undo breaks these assumptions and will sometimes cause exceptions.
It is also not a natural expectation to expect suggestions based on changes made from undo.
Therefore we should exempt changes made via undo from making queries.

Description of changes:

• Adds command listener to listen for undo command in autotrigger document listener.

Test:
Shown below:

• Insertion done via undo does not trigger queries
• Insertion done via normal input remains functional
  

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