Add Feature flag for language-directory (#3316)

* Add temporary language-directory dependency

* Add static provider for language directory

* Add language directory flag

* Reroute language-directory for testing

* Remove unused export

* Configure temporary yarn directory

* Refactor out LegacyButton behaviour

* Manage language-directory languages in redux

* Update ChapterSelect for language directory

* Update package directory

* Add temporary example conductor urls

* Format via prettier

* Fix tsc error

* Remove js map

* Remove unnecessary type conversion

* update pie's evaluator

---------

Co-authored-by: Martin Henz <henz@comp.nus.edu.sg>
Co-authored-by: Richard Dominick <34370238+RichDom2185@users.noreply.github.com>
Co-authored-by: dingfeng <fengDing0321@gmail.com>

Author: 4 people

package.json

@@ -41,6 +41,7 @@
     "@reduxjs/toolkit": "^1.9.7",
     "@sentry/react": "^10.5.0",
     "@sourceacademy/c-slang": "^1.0.21",
+    "@sourceacademy/language-directory": "https://github.com/loyaltypollution/language-directory.git#866cc934372a19e514af0025947ce7f1f5a6e1fc",
     "@sourceacademy/sharedb-ace": "2.1.1",
     "@sourceacademy/sling-client": "^0.1.0",
     "@szhsin/react-menu": "^4.0.0",
@@ -67,7 +68,6 @@
     "js-slang": "^1.0.85",
     "js-yaml": "^4.1.0",
     "konva": "^9.2.0",
-    "language-directory": "https://github.com/source-academy/language-directory.git",
     "lodash": "^4.17.21",
     "lz-string": "^1.4.4",
     "mdast-util-from-markdown": "^2.0.0",