[FEATURE] Update Langium to 2.0

[rhazn]

UAC

• Langium is updated to version 2 https://github.com/eclipse-langium/langium/blob/main/packages/langium/CHANGELOG.md#v200-aug-2023

Notes

• Consider if it is easier to do 1.3 first [FEATURE] Update Langium to 2.0 #427

Definitions of Done

• A PR has been opened and accepted
• All user acceptance criteria are met
• All tests are passing

[georg-schwarz]

Thru some experiments, I found the following links very helpful for a future migration

• you can create commonjs and esm outputs in parallel for a potentially gradual migration to esm: https://www.sensedeep.com/blog/posts/2021/how-to-create-single-source-npm-module.html
• there is a cli tool that does most of the import rewriting for you: https://github.com/bennycode/ts2esm
• I assume jest needs to be reconfigured as well: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support/
• I assume eslint needs to be reconfigured as well. Whether we need additional migration specific eslint rules should be discussed as well: https://gist.github.com/Jaid/164668c0151ae09d2bc81be78a203dd5