Improve find in terminal

[Tyriar]

Basic find in terminal functionality was added in #15198. Here are some of the improvements we can make

• Highlight all instances of term in current viewport Moved to Terminal Find: Highlight all instances of term in current viewport and don't manipulate selection #134790
• Use a different selection type so that regular selection isn't hijacked, plus a color with a higher contrast can be used. Moved to Terminal Find: Highlight all instances of term in current viewport and don't manipulate selection #134790
• Find multiple instances on the same line
• Find terms that are wrapped across 2 lines
• Options: regex, case sensitivity, match word
• Add "No results" label, need to think about what to show in the gap when there are results. We probably shouldn't be searching the entire buffer when we don't have to for performance reasons. Moved to Terminal Find: Show result count #134791
• Add animation to terminal find widget just like it does on editor

Upstream improve find API issue: xtermjs/xterm.js#705

/cc @rebornix

[noamyogev84]

@Tyriar is this something I can try to work on? if so, some code pointers?

[Tyriar]

@noamyogev84 some of this got fixed recently: #58826

For the other parts, you can refer to the individual issues in xterm.js: https://github.com/xtermjs/xterm.js/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22+label%3Aaddon+search+addon

The search "addon" is located in ./src/addons/search in the xterm.js repo.

[dalDevelo]

I've just come to add my voice for improved terminal features in VSCode. My main issues at the lack of ability to adjust the 'found search term' highlighting. It would be great if you could adjust this, even if it was to pick from a selection of pre-defined highlight colours. The current grey highlighting is not visible enough IMO. I often struggle to see the found term quickly. Alternatively, a flashing 'on selection' highlight would be helpful as the macOS terminal has...

[Yanpas]

KDE's Konsole has the most handy search. The most needed feature is highlighting all matches.

[Tyriar]

Moved remaining items into more actionable individual feature requests #134791, #134790