chore: Extract languages from zed crate (#8270)

- Moves languages module from `zed` into a separate crate. That way we
have less of a long pole at the end of compilation.
- Removes moot dependencies on editor/picker. This is totally harmless
and might help in the future if we decide to decouple picker from
editor.

Before:
```
Number of crates that depend on 'picker' but not on 'editor': 1
Total number of crates that depend on 'picker': 13
Total number of crates that depend on 'editor': 30
```
After:
```
Number of crates that depend on 'picker' but not on 'editor': 5
Total number of crates that depend on 'picker': 12
Total number of crates that depend on 'editor': 26
```
The more crates depend on just picker but not editor, the better in that
case.

Release Notes:

- N/A

crates/languages/src/javascript/overrides.scm

@@ -0,0 +1,18 @@
+(comment) @comment
+
+[
+  (string)
+  (template_string)
+] @string
+
+[
+  (jsx_element)
+  (jsx_fragment)
+] @element
+
+[
+  (jsx_opening_element)
+  (jsx_closing_element)
+  (jsx_self_closing_element)
+  (jsx_expression)
+] @default