Add LM Studio support to the Assistant (#23097)

#### Release Notes:

- Added support for [LM Studio](https://lmstudio.ai/) to the Assistant.

#### Quick demo:


https://github.com/user-attachments/assets/af58fc13-1abc-4898-9747-3511016da86a

#### Future enhancements:
- wire up tool calling (new in [LM Studio
0.3.6](https://lmstudio.ai/blog/lmstudio-v0.3.6))

---------

Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>

crates/ui/src/components/icon.rs

@@ -116,6 +116,7 @@ pub enum IconName {
     AiAnthropic,
     AiAnthropicHosted,
     AiGoogle,
+    AiLmStudio,
     AiOllama,
     AiOpenAi,
     AiZed,