[MM-55152] Add new Desktop API endpoints, improve preload script, some clean-up (#2900)

* Add constants for app info, add to API

* Migrate history button

* Converted calls API over to context bridge, removed some unnecessary logging

* Convert to TS, add types for web app to consume

* Fix tests, prune

* Fix lint

* More changes to support the legacy API

* Force legacy code off, add support for unreads/mentions/expired through the API

* Fix issues with cross-tab login, removed need for log in/log out signalling

* Fixed test, typos

* Change package name for types

* Add some other stuff to the types

* PR feedback

* More feedback

* Use npm package

* Change types and API to provide off listeners

* Version number

* Lock

* Fix typo

* Add sessionID for calls

api-types/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@mattermost/desktop-api",
+  "version": "5.7.0-2",
+  "description": "Shared types for the Desktop App API provided to the Web App",
+  "keywords": [
+    "mattermost"
+  ],
+  "homepage": "https://github.com/mattermost/desktop",
+  "license": "MIT",
+  "files": [
+    "lib"
+  ],
+  "main": "lib/index.js",
+  "types": "lib/index.d.ts",
+  "repository": {
+    "type": "git",
+    "url": "github:mattermost/desktop",
+    "directory": "api-types"
+  },
+  "peerDependencies": {
+    "typescript": "^4.3"
+  },
+  "peerDependenciesMeta": {
+    "typescript": {
+      "optional": true
+    }
+  },
+  "scripts": {
+    "build": "tsc --build --verbose",
+    "run": "tsc --watch --preserveWatchOutput",
+    "clean": "rm -rf tsconfig.tsbuildinfo ./lib"
+  }
+}