Cody: add highlighted text from editor to prompt

[abeatrix]

RE: https://sourcegraph.slack.com/archives/C052G9Y5Y8H/p1683316126807689

Add selected text from editor automatically to the end of the prompt when detected.

Test plan

To test, you can highlight text from your editor, and then ask cody about the selected text without copying and pasting the code to the chat box:

[sourcegraph-buildkite]

Bundle size report 📦

Initial size	Total size	Async size	Modules
0.00% (0.00 kb)	0.00% (+0.34 kb)	0.00% (+0.34 kb)	0.00% (0)

Look at the Statoscope report for a full comparison between the commits 7512527 and 6dc780f or learn more.

Open explanation

• Initial size is the size of the initial bundle (the one that is loaded when you open the page)
• Total size is the size of the initial bundle + all the async loaded chunks
• Async size is the size of all the async loaded chunks
• Modules is the number of modules in the initial bundle

[sourcegraph-bot]

📖 Storybook live preview

[philipp-spiess]

This is awesome! I wonder if we should move it into the getEditorContext part of the chat question recipe though? Reason being that if you have a very large selection (like a 10k file with cmd + a) it might not be super practical to always add the selection context and rather do it in the same way we add the current viewport. WDYT?

[abeatrix]

This is awesome! I wonder if we should move it into the getEditorContext part of the chat question recipe though? Reason being that if you have a very large selection (like a 10k file with cmd + a) it might not be super practical to always add the selection context and rather do it in the same way we add the current viewport. WDYT?

Update: that was a really good point and idea. I've moved it into its own context template that's reusable! Thanks for the review 😍