Fix race condition between auto-indent and on-type-formatting (#32005)

This PR addresses to fix (#31308) a race condition where auto-indent (in
buffer.cs) and on-type-formatting (in lsp_store.rs) concurrently
calculate indentation using the same buffer snapshot.

Previous Solution (Abandoned): 
https://github.com/zed-industries/zed/pull/31340

Final Solution:
Delay applying on-type-formatting until auto-indent is complete.

Issue:

If AutoindentMode finishes first, formatting works correctly. If
"Formatting on typing" starts before AutoindentMode completes, it
results in double indentation.

Closes #31308

Release Notes:

- Fixed a race condition resulting in incorrect buffer contents when combining auto-indent and on-type-formatting

crates/project/src/lsp_store.rs

@@ -5098,17 +5098,30 @@ impl LspStore {
                 .as_ref(),
             )
         });
-        self.request_lsp(
-            buffer.clone(),
-            LanguageServerToQuery::FirstCapable,
-            OnTypeFormatting {
-                position,
-                trigger,
-                options,
-                push_to_history,
-            },
-            cx,
-        )
+
+        cx.spawn(async move |this, cx| {
+            if let Some(waiter) =
+                buffer.update(cx, |buffer, _| buffer.wait_for_autoindent_applied())?
+            {
+                waiter.await?;
+            }
+            cx.update(|cx| {
+                this.update(cx, |this, cx| {
+                    this.request_lsp(
+                        buffer.clone(),
+                        LanguageServerToQuery::FirstCapable,
+                        OnTypeFormatting {
+                            position,
+                            trigger,
+                            options,
+                            push_to_history,
+                        },
+                        cx,
+                    )
+                })
+            })??
+            .await
+        })
     }
 
     pub fn code_actions(