Update @kusto/language-service-next (#127)

Update [@kusto/language-service-next](https://www.npmjs.com/package/@kusto/language-service-next/v/11.5.3?activeTab=versions) to the 11.5.* line, which was published 3 months ago and is getting regular updates. This dependency was previously pinned to an old pre-release version (0.0.28-rc.1) which was used during the original hackathon back in 2019 that this extension was created during. 

Fixes bug #5
Also fixes bug #126 in passing.

Additional changes:
- some updates to deal with some breaking changes made to types - nothing too scary, mostly types getting upgraded to be nullable, or constructors changing order and therefore changing names
- remove hand-written type definitions that were needed to get the typescript build passing (e.g. kusto-language-server/server/out/Kusto.Language.Bridge.min.js)
- remove peer dependencies that were needed to patch things up back then (the legacy language service package, the monaco package). These are no longer needed anymore - everything is included in the latest language service package.
- update the typescript version in use to 5.* - this is parity with the [Azure/monaco-kusto](https://www.npmjs.com/package/@kusto/monaco-kusto?activeTab=readme#monaco-kusto) package, which is a more well-supported sibling of this one and is worth referring to. 
- update the node version used in CI to 20 (was: 12)
- update `@types/node`, needed for CI to pass during `npm run vscode:prepublish`, see https://stackoverflow.com/questions/57331779/typescript-duplicate-identifier-iteratorresult

Testing:
- Launches without crashing
- Format document: seems to be working, and bug #126 no longer repros
- Autocomplete: seems to be working
- Hover info: seems to be working

.github/workflows/kusto-language-server-pr-validation.yml

@@ -22,6 +22,6 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 20
       - run: npm ci
       - run: npm run vscode:prepublish

.github/workflows/kusto-language-server-publish.yml

@@ -22,7 +22,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 20
 
       - name:  'Automated Version Bump'
         uses:  ./.github/actions/gh-action-bump-version-master

kusto-language-server/JANK_CLEANUP.md

@@ -1,7 +1,4 @@
-- .js files checked into server/out should be included in server/src instead, and gulp should be used to copy them into /out as a post-build task (after tsc -watch runs each time)
-   - bridge.min.js, Kusto.Language.Bridge.min.js
 - File replacement for formatting goes from 0,0 to Number.MAX_VALUE,MAX_VALUE - If a file happened to be bigger it wouldn't format properly. (Would also be oom exception)
-- _items, Items._items
 - listener.newState == 2
 - .csl files with .create-or-alter function must NOT have a blank line between the .create-or-alter statement and the function name, and must NOT have a blank line between the function name and the opening {, so that the whole thing is one block
 - .csl files with .create-or-alter function MUST have a blank line after the opening { and the first line of query, otherwise the whole thing is one block