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/css/brackets.scm

@@ -0,0 +1,3 @@
+("(" @open ")" @close)
+("[" @open "]" @close)
+("{" @open "}" @close)

crates/languages/src/css/config.toml

@@ -0,0 +1,14 @@
+name = "CSS"
+grammar = "css"
+path_suffixes = ["css"]
+autoclose_before = ";:.,=}])>"
+brackets = [
+    { start = "{", end = "}", close = true, newline = true },
+    { start = "[", end = "]", close = true, newline = true },
+    { start = "(", end = ")", close = true, newline = true },
+    { start = "\"", end = "\"", close = true, newline = false, not_in = ["string", "comment"] },
+    { start = "'", end = "'", close = true, newline = false, not_in = ["string", "comment"] },
+]
+word_characters = ["-"]
+block_comment = ["/* ", " */"]
+prettier_parser_name = "css"

crates/languages/src/css/highlights.scm

@@ -0,0 +1,78 @@
+(comment) @comment
+
+[
+  (tag_name)
+  (nesting_selector)
+  (universal_selector)
+] @tag
+
+[
+  "~"
+  ">"
+  "+"
+  "-"
+  "*"
+  "/"
+  "="
+  "^="
+  "|="
+  "~="
+  "$="
+  "*="
+  "and"
+  "or"
+  "not"
+  "only"
+] @operator
+
+(attribute_selector (plain_value) @string)
+
+(attribute_name) @attribute
+(pseudo_element_selector (tag_name) @attribute)
+(pseudo_class_selector (class_name) @attribute)
+
+[
+  (class_name)
+  (id_name)
+  (namespace_name)
+  (property_name)
+  (feature_name)
+] @property
+
+(function_name) @function
+
+(
+  [
+    (property_name)
+    (plain_value)
+  ] @variable.special
+  (#match? @variable.special "^--")
+)
+
+[
+  "@media"
+  "@import"
+  "@charset"
+  "@namespace"
+  "@supports"
+  "@keyframes"
+  (at_keyword)
+  (to)
+  (from)
+  (important)
+]  @keyword
+
+(string_value) @string
+(color_value) @string.special
+
+[
+  (integer_value)
+  (float_value)
+] @number
+
+(unit) @type
+
+[
+  ","
+  ":"
+] @punctuation.delimiter

crates/languages/src/css/indents.scm

@@ -0,0 +1 @@
+(_ "{" "}" @end) @indent

crates/languages/src/css/overrides.scm

@@ -0,0 +1,2 @@
+(comment) @comment
+(string_value) @string