add: the start of dart lang support (#2671)

Hello, hopefully I did these first steps right and I would like some
rough guidance on adding the subsequent things like snippets or any
other essentials for dart support, thanks!

## Checklist

- [ ] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [ ] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [ ] I have not broken the cheatsheet

---------

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

data/fixtures/scopes/dart/ifStatement.scope

@@ -0,0 +1,19 @@
+foo() {
+  if (true) { }
+}
+---
+
+[Content] =
+[Domain] = 1:2-1:15
+    >-------------<
+1|   if (true) { }
+
+[Removal] = 1:0-1:15
+  >---------------<
+1|   if (true) { }
+
+[Leading delimiter] = 1:0-1:2
+  >--<
+1|   if (true) { }
+
+[Insertion delimiter] = "\n"

data/fixtures/scopes/dart/list.scope

@@ -0,0 +1,17 @@
+final list = [1,2,3];
+---
+
+[Content] =
+[Domain] = 0:13-0:20
+               >-------<
+0| final list = [1,2,3];
+
+[Removal] = 0:12-0:20
+              >--------<
+0| final list = [1,2,3];
+
+[Leading delimiter] = 0:12-0:13
+              >-<
+0| final list = [1,2,3];
+
+[Insertion delimiter] = " "

data/fixtures/scopes/dart/map.scope

@@ -0,0 +1,25 @@
+  final map = {
+    'hi': 1,
+  };
+---
+
+[Content] =
+[Domain] = 0:14-2:3
+                >-
+0|   final map = {
+1|     'hi': 1,
+2|   };
+   ---<
+
+[Removal] = 0:13-2:3
+               >--
+0|   final map = {
+1|     'hi': 1,
+2|   };
+   ---<
+
+[Leading delimiter] = 0:13-0:14
+               >-<
+0|   final map = {
+
+[Insertion delimiter] = " "

data/playground/dart.dart

@@ -0,0 +1,9 @@
+foo() {
+  if (true) {}
+
+  final list = [1, 2, 3];
+
+  final map = {
+    'hi': 1,
+  };
+}

packages/common/src/scopeSupportFacets/dart.ts

@@ -0,0 +1,11 @@
+import type { LanguageScopeSupportFacetMap } from "./scopeSupportFacets.types";
+import { ScopeSupportFacetLevel } from "./scopeSupportFacets.types";
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const { supported, unsupported, notApplicable } = ScopeSupportFacetLevel;
+
+export const dartScopeSupport: LanguageScopeSupportFacetMap = {
+  ifStatement: supported,
+  list: supported,
+  map: supported,
+};

packages/common/src/scopeSupportFacets/languageScopeSupport.ts

@@ -4,6 +4,7 @@ import { clojureScopeSupport } from "./clojure";
 import { cppScopeSupport } from "./cpp";
 import { csharpScopeSupport } from "./csharp";
 import { cssScopeSupport } from "./css";
+import { dartScopeSupport } from "./dart";
 import { goScopeSupport } from "./go";
 import { htmlScopeSupport } from "./html";
 import { javaScopeSupport } from "./java";
@@ -35,6 +36,7 @@ export const languageScopeSupport: StringRecord<LanguageScopeSupportFacetMap> =
     cpp: cppScopeSupport,
     csharp: csharpScopeSupport,
     css: cssScopeSupport,
+    dart: dartScopeSupport,
     go: goScopeSupport,
     html: htmlScopeSupport,
     java: javaScopeSupport,

packages/cursorless-org-docs/src/docs/user/languages/dart.mdx

@@ -0,0 +1,5 @@
+import Language from "./Language";
+
+# dart
+
+<Language languageId="dart"></Language>

queries/dart.scm

@@ -0,0 +1,18 @@
+
+;;!! if () {}
+;;!  ^^^^^^^^
+(if_statement) @ifStatement
+
+;;!! [ 0 ]
+;;!  ^^^^^
+[
+  (list_literal)
+  (list_pattern)
+] @list
+
+;;!! { value: 0 }
+;;!  ^^^^^^^^^^^^
+[
+  (set_or_map_literal)
+  (map_pattern)
+] @map