Selecting and copying text with cursor highlight

[supreme-gg-gg]

Is your feature request related to a problem? Please describe.
In opencode, you can just highlight a text with cursor (including multiline) and it auto copies to your clipboard. Not a super common use case feature but would be nice-to-have for some people. Again, we're not building coding CLI here, but even a messenger TUI can benefit from easier text copying.

Describe the solution you'd like

1. Detect mouse highlight events (medium)
2. Find out the text underneath it (hard, not entirely sure how, this would be easy to do for input bar, but might be hard otherwise)
3. Copy to clipboard automatically (easy)

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
This would build upon the work in #279. However, that PR did not directly support mouse highlight events, only scrolling and clicking. Figuring out what text is highlighted will be non-trivial if we want the user to be able to highlight any messages sent. I'll post my thoughts below if any come up.

[endernoke]

Native cursor highlight was working (on Windows terminal at least) as of commit 8b5cf7ea1856f314989182e3d24d47a0dcfb1f03 i.e. before the mouse PR landed.

I suspect this is caused by the terminal not handling cursor movement while it reports mouse movement.

Find out the text underneath it (hard, not entirely sure how, this would be easy to do for input bar, but might be hard otherwise)

I think a generalizable solution for this is near impossible on userland, as we need to inspect the rendered frame buffer. Perhaps this might go in as a feature request for ink, but then ink probably has to implement mouse events upstream.

Alternatively, we can have a :copy command which copies message content to the clipboard, which would solve a major use case.

[supreme-gg-gg]

Native cursor highlight was working (on Windows terminal at least) as of commit 8b5cf7ea1856f314989182e3d24d47a0dcfb1f03 i.e. before the mouse PR landed.

Might be due to our mouse mode taking over now with those control sequences 😭 As the saying goes, with more power comes more responsibility lol (and more tech debt...)

Agreed that :copy will be a quick and easy solution for now. Perhaps it's worth investigating how OpenCode does it (likely it utilizes some on highlight hook from the components in OpenTUI?) or ask AI to create a report on that and see if we can somehow "get inspired" again