Move changes to v1alpha18 and revert v1 (#346)

closes #344

Author: tiyash-basu-frequenz

RELEASE_NOTES.md

@@ -2,27 +2,52 @@
 
 ## Summary
 
-This release introduces significant **breaking changes** to align with the `frequenz-api-common v0.8.0` release. Key updates include a more unified power-setting RPC, numerous symbol renames for consistency, and updated dependency requirements.
+This release introduces a new preview API version, `v1alpha18`, alongside the stable `v1` API, and updates the underlying `frequenz-api-common` dependency to `v0.8.0`.
+
+The `v1` API remains unchanged to ensure backward compatibility. All new features, including a more unified power-setting RPC and alignment with `frequenz-api-common v0.8.0`, are available exclusively in the new `v1alpha18` package.
 
 -----
 
-## Upgrading
+## Stable `v1` API
+
+The `v1` API is stable and has **not** been changed in this release. Users currently on `v1` do not need to make any changes, beyond potentially updating python dependencies as described below.
+
+The upgrade to `frequenz-api-common v0.8.0` does not affect the `v1` API, and it remains fully compatible with existing implementations.
+
+-----
+
+## New `v1alpha18` Preview API
+
+A new package, `frequenz.api.microgrid.v1alpha18`, has been introduced to provide access to the latest features. The `v1alpha18` API introduces a more streamlined and robust interface compared to the stable `v1` API.
+
+-----
+
+## Upgrading to the `v0.18.0` release
 
 ### 1. Dependency Updates
 
-Your project's dependencies may need to be updated.
+Despite the `v1` API remaining unchanged, your project's dependencies may need to be updated, due to the following python dependency updates:
+
+  * The minimum supported version of `protobuf` is now `6.31.1`.
+  * The minimum supported version of `grpcio` is now `1.72.1`.
+
+-----
+
+## Upgrading to the `v1alpha18` API
+
+Alongside upgrading to the `v0.18.0` release, you can also upgrade to the new `v1alpha18` API, which includes several significant changes and improvements.
+
+### 1. Dependency Updates
 
-  * The minimum supported version of `protobuf` is now **`6.31.1`**.
-  * The minimum supported version of `grpcio` is now **`1.72.1`**.
-  * The `frequenz-api-common` dependency has been updated from `v0.6.1` to **`v0.8.0`**. Please consult the common API's release notes for details:
-      * [`v0.7.0` release notes](https://github.com/frequenz-floss/frequenz-api-common/releases/tag/v0.7.0)
-      * [`v0.8.0` release notes](https://github.com/frequenz-floss/frequenz-api-common/releases/tag/v0.8.0)
+**frequenz-api-common v0.8.0**: The `frequenz-api-common` dependency has been updated from `v0.6.1` to `v0.8.0`. The `v1alpha18` API uses the `frequenz.api.common.v1alpha8` API from the `frequenz-api-common v0.8.0` dependency, which includes several improvements and changes compared to the previous version. Please consult the release notes in `frequenz-api-common`'s for details:
+  * [`v0.7.0` release notes](https://github.com/frequenz-floss/frequenz-api-common/releases/tag/v0.7.0)
+  * [`v0.8.0` release notes](https://github.com/frequenz-floss/frequenz-api-common/releases/tag/v0.8.0)
 
 -----
 
 ### 2. Removals
 
-  * **Sensor categories**: These have been removed entirely, aligning with the underlying `frequenz-api-common` dependency.
+  * **Sensor categories**: These have been removed entirely, aligning with the underlying `frequenz-api-common v0.8.0` dependency.
   * **RPCs**: `SetComponentPowerActive` and `SetComponentPowerReactive` have been removed. Use the new `SetElectricalComponentPower` RPC instead (see below).
 
 -----