Query multiple LSPs for more types of requests (#29359)

This fixes an issue where lower-priority language servers cannot provide
contentful responses even when the first capable server returned empty
responses.

Most of the diffs are copypasted since the existing implementations were
also copypasted.

Release Notes:

- Improved Go to Definition / Declaration / Type Definition /
Implementation and Find All References to include all results from
different language servers

crates/editor/src/editor.rs

@@ -21944,10 +21944,10 @@ impl SemanticsProvider for Entity<Project> {
         cx: &mut App,
     ) -> Option<Task<Result<Vec<LocationLink>>>> {
         Some(self.update(cx, |project, cx| match kind {
-            GotoDefinitionKind::Symbol => project.definition(&buffer, position, cx),
-            GotoDefinitionKind::Declaration => project.declaration(&buffer, position, cx),
-            GotoDefinitionKind::Type => project.type_definition(&buffer, position, cx),
-            GotoDefinitionKind::Implementation => project.implementation(&buffer, position, cx),
+            GotoDefinitionKind::Symbol => project.definitions(&buffer, position, cx),
+            GotoDefinitionKind::Declaration => project.declarations(&buffer, position, cx),
+            GotoDefinitionKind::Type => project.type_definitions(&buffer, position, cx),
+            GotoDefinitionKind::Implementation => project.implementations(&buffer, position, cx),
         }))
     }