input: Fix wrong font being used in Input.

[zanmato]

Closes #1665

Description

When Input::new().font_family("font") is used, the font hasn't been applied yet in Input::render, therefore the text_wrapper will calculate using the wrong font. This is why it's working when the font is added to the parent element.

The fix moves the state update to element prepaint, where window.text_style() has the correct styles. The only downside is that there are now one additional state update.

Screenshot

Before	After

How to Test

Use some wide font, like IBM Plex Mono. Apply it to Input::new(&some_state).font_family("IBM Plex Mono") where the input state has soft_wrap. Here is a diff for textarea_story.rs.

diff --git a/crates/story/src/textarea_story.rs b/crates/story/src/textarea_story.rs
index f2c63d44..bd5cbb31 100644
--- a/crates/story/src/textarea_story.rs
+++ b/crates/story/src/textarea_story.rs
@@ -77,9 +77,9 @@ impl TextareaStory {
 
         let textarea_no_wrap = cx.new(|cx| {
             InputState::new(window, cx)
-                .multi_line(true)
                 .rows(6)
-                .soft_wrap(false)
+                .multi_line(true)
+                .soft_wrap(true)
                 .default_value("This is a very long line of text to test if the horizontal scrolling function is working properly, and it should not wrap automatically but display a horizontal scrollbar.\nThe second line is also very long text, used to test the horizontal scrolling effect under multiple lines, and you can input more content to test.\nThe third line: Here you can input other long text content that requires horizontal scrolling.\n")
         });
 
@@ -195,7 +185,7 @@ impl Render for TextareaStory {
             .child(
                 section("Auto Grow")
                     .max_w_md()
-                    .child(Input::new(&self.textarea_auto_grow)),
+                    .child(Input::new(&self.textarea_auto_grow).font_family("IBM Plex Mono")),
             )
             .child(
                 section("Auto Grow with No Wrap")

Checklist

• [x] I have read the CONTRIBUTING document and followed the guidelines.
• [x] Reviewed the changes in this PR and confirmed AI generated code (If any) is accurate.
• [x] Passed cargo run for story tests related to the changes.
• [ ] Tested macOS, Windows and Linux platforms performance (if the change is platform-specific)