Move pages under tldr, lint run.sh, update docs

tldr/dart

@@ -0,0 +1,33 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# dart
+
+> Manage Dart projects.
+> More information: <https://dart.dev/tools/dart-tool>.
+
+- Initialize a new Dart project in a directory of the same name:
+
+`dart create {{project_name}}`
+
+- Run a Dart file:
+
+`dart run {{path/to/file.dart}}`
+
+- Download dependencies for the current project:
+
+`dart pub get`
+
+- Run unit tests for the current project:
+
+`dart test`
+
+- Update an outdated project's dependencies to support null-safety:
+
+`dart pub upgrade --null-safety`
+
+- Compile a Dart file to a native binary:
+
+`dart compile exe {{path/to/file.dart}}`