Add breaking changes file into What's New (#3453)

* initial commit of file content

Signed-off-by: Andrew Jandacek <[email protected]>

* add breaking changes file to sidebars.js

Signed-off-by: Andrew Jandacek <[email protected]>

* Add more information

Signed-off-by: Jakub Balhar <[email protected]>

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Signed-off-by: Andrew Jandacek <[email protected]>
Signed-off-by: Jakub Balhar <[email protected]>
Co-authored-by: Jakub Balhar <[email protected]>

docs/whats-new/breaking-changes-v3.md

@@ -0,0 +1,87 @@
+# Breaking Changes and Important Updates in Zowe v3
+
+The upcoming release of Zowe v3 will bring a range of major changes in Zowe functionality. Review this article for details about changes to various Zowe components to be introduced in Zowe v3.
+
+## API Mediation Layer (API ML)
+
+### Breaking Changes to API ML
+
+* Authentication endpoints will not support the route `/api/v1/gateway`, and instead will support only `/gateway/api/v1`
+* Spring Enabler will be updated to Spring Boot 3 and Spring 6. Spring Boot 2 and Spring 5 versions will no longer be supported.
+* Datasets API will be archived
+* Jobs API will be archived
+* Metrics service will be archived
+* IMS API will be archived
+* Java 17 will be required for the API Mediation Layer to run
+* z/OSMF in version V2R5 with APAR PH12143 applied
+* Configuration of keyrings will require transformation from `safkeyring:////` to `safkeyring://`
+
+### Important updates
+
+The current API Gateway contains Authentication and Authorization Services. This service will be separated as a standalone service. This is the only API Mediation Layer service that needs z/OS directly
+
+## Application Framework
+
+### Breaking changes
+
+* Updating Angular to Version 16 from Version 12
+* Removing the core-js dependency
+* Updating Webpack to version 5
+* Updating Typescript to 4.9
+
+## CLI
+
+### Breaking changes
+
+* Introducing a new format for error messages to improve clarity
+* Removing V1 profile support
+* Removing deprecated items - [CLI](https://github.com/zowe/zowe-cli/issues/1694) and [Imperative](https://github.com/zowe/zowe-cli/issues/1873)
+
+### Pre-release availability
+
+* V3 pre-release versions are available via [npm](https://www.npmjs.com/package/@zowe/cli?activeTab=readme) under the 'next' tag
+
+## Explorer for Intellij
+
+### Important updates
+
+* Explorer for Intellij will be part of the Zowe Core
+* Working with USS Files
+* Working with Data Sets
+* Working with JES Working Sets
+* Interactive TSO Console
+
+## Explorer for Visual Studio Code
+
+### Breaking changes
+
+* Removing V1 profile support
+* Removing deprecated items - [Explorer for VSCode](https://github.com/zowe/vscode-extension-for-zowe/issues/2238)
+* Changing profile creation menus
+* Storing extension settings in local storage
+
+### Important updates
+
+* Storing persistent settings in local storage
+* Comparing files in MVS view, the USS view, and across the two views
+
+### Pre-release availability
+
+* V3 pre-release versions are available via [GitHub releases](https://github.com/zowe/vscode-extension-for-zowe/releases) or via the [Open VSX Registry](https://open-vsx.org/extension/Zowe/vscode-extension-for-zowe).
+
+## Installation and Packaging
+
+### Breaking changes
+
+* Dropping the original V2 configuration management, `zowe.useConfigmgr=false`. (The Configuration Manager remains as the only supported method for configuring Zowe)
+
+### Important updates
+
+* Removing the dependency on Node.js for configuration
+* Introducing _ZEN_, a wizard to simplify configuration via the UI
+
+## ZSS
+
+### Breaking changes
+
+* Run by default in 64 bit mode, `components.zss.agent.64bit=true`. 31-bit plugins cannot run in 64-bit ZSS, so you need to compile your plugins for the version of ZSS to be used. Note that only one version of ZSS can run at a time.

sidebars.js

@@ -28,6 +28,7 @@ module.exports = {
       ],
     },
     "whats-new/zowe-v3-office-hours",
+    "whats-new/breaking-changes-v3",
   ],
   "getting-started": [
     {