Add optional initial_query to suggester

[mnaoumov]

Fixes #555

[Zachatoo]

Could you also update the docs as part of this PR?

[AB1908]

Can someone remind me how this is different from placeholder? Also, for conformity, should we rename it to default_value?

[tektrip-biggles]

Can someone remind me how this is different from placeholder? Also, for conformity, should we rename it to default_value?

My understanding is that placeholder simply appears in the prompt box as an aide memoire, whereas default_value would be a valid option from the list presented to the user. E.g. I want to be prompted for task priority so I might use:

<% tp.system.suggester(
  (item) => item, 
  ["1: Highest", "2: High", "3: Medium", "4: Low", "6: Lowest"], 
  false, 
  "Priority",
   5, 
  "3: Medium") 
%>

This way if I press enter as soon as the prompt appears, I'll select "3: Medium" as priority instead of "1: Highest" as currently. This saves two keypresses in the average case and four keypresses in the worst case, which can add up quickly when, say, adding a ton of task notes.

Don't suppose there's any chance this will make its way into main any time soon btw?