Add Custom Chat Model inputs not sanitized

[i13-ctflora]

• Disable all other plugins besides Copilot (required)
• Screenshot of note + Copilot chat pane + dev console added (required)

Copilot version: v2.8.0

Describe how to reproduce
In the Settings -> Model -> Add Custom Model dialog, inputs are not trimmed. I was trying to add Perplexity as a custom model, and instead of typing the Model Name manually I was copy/pasting it from their site. Apparently, I was accidentally getting an extra space at the end of the model name. When I tried to verify the model, it failed with a 404 error. It took me almost 30 minutes and adding, testing, deleting, and repeating before I finally saw that tiny space.

Expected behavior
I'd like to see the inputs on this screen trimmed (left and right) of extra white space to avoid this issue in the future. I know it's entirely my fault, but my process is probably pretty common and this fix could potentially prevent future heartache, lol.

Screenshots
On the perplexity Supported Models page, if you double-click the model to select it, you can see that it includes an extra space at the end:

And on pasting into the "Add Custom Chat Model" dialog, you can see the tiny space between the last letter and the cursor:

Additional context
Again, I totally understand that this is my fault, but sanitizing the inputs on the dialog might make a smoother experience for other users because of the extra space in the selection on the perplexity website.