Epic: Search v2

Description of the new feature/enhancement

[Original Issue: #605] [Original Spec: #3299] [Initial PR: #3590]

Terminal text search has already realizes single tab case sensitive/insensitive forward/backward search. In phase 2, we are considering these new features:

• Add "Find" button in dropdown menu to trigger search. Now the search dialog is launched by key bindings, we may need to consider binding the dialog to a button in dropdown menu for mouse only operations.
  • sorta in #13055. Close enough.
• High-light while you type. Emphasizing all the matches in the buffer with an outline or selection with another color. This provides a clearer view of the searched text.
  • #7561 Feature Request: Highlight all finding
• #6319 No results notification (or reveal number of results)
  • in #14045
• #7695 next/previous search key bindings
• #8307 Selected text should populate search box
• #8274 Add capability to insert matched hit
• #1527 Display "find" matches in the scrollbar, #8631
  • in #14045
• Pressing next/previous match keybindings should move to the next needle, even if the dialog is closed. (Maybe it should auto display the dialog)
  • Mentioned in #8522 and #8588
• It'd be cool if there was a shadow underneath the search dialog, like there is for the command palette.
  • Mentioned in https://github.com/microsoft/terminal/pull/11105#issuecomment-911929402
  • Fixed in #12913
• Regular expression (regex) match. This is a useful search pattern and is implemented in some editors.
  • first proto in #9228
  • Will be effortless after #15858 merges
  • merged in #17316, in 1.22
• Add size handle. Some text editors let the user resize the search box, and there is a size handle on the left side of the search box. This helps user when they search for long text.
• #5314 Fuzzy Search
  • Go look at #16586
• #4407
• Search from all tabs. In phase one search are limited within one Terminal window. However, the community also requests search from all tabs. This may require a big change to the search algorithm.
  • Depends on #997 by all accounts
• Search history. Sometimes users would do the same search for several times, thus, storing the search history is useful.

Also related, from #5001:

• Add a setting to configure the regex used to detect patterns
• Allow "hyperlink" matching for arbitrary patterns and adding custom handlers #8849
  • Theoretically, this could supersede #7562
  • Should be self-consistent with #8294
• Control the styling of hyperlinks - attributes used for autodetected hyperlinks, and then different attributes for hovered ones #8294

Review the unchecked search enhancements and their referenced issues, especially #5314/#16586 for fuzzy search and #997 for searching across tabs. The epic is complete when the selected search feature has a defined implementation scope and its corresponding behavior is implemented and verified.