README: Mention the two possible docker images

.github/workflows/docker.yml

@@ -13,10 +13,14 @@ jobs:
     strategy:
       matrix:
         image:
+          # We build two images, `grist-oss` and `grist`.
+          # See https://github.com/gristlabs/grist-core?tab=readme-ov-file#available-docker-images
           - name: "grist-oss"
             repo: "grist-core"
           - name: "grist"
             repo: "grist-ee"
+          # For now, we build it twice, with `grist-ee` being a
+          # backwards-compatible synoym for `grist`.
           - name: "grist-ee"
             repo: "grist-ee"
     steps:

.github/workflows/docker_latest.yml

@@ -26,10 +26,14 @@ jobs:
         python-version: [3.9]
         node-version: [18.x]
         image:
+          # We build two images, `grist-oss` and `grist`.
+          # See https://github.com/gristlabs/grist-core?tab=readme-ov-file#available-docker-images
           - name: "grist-oss"
             repo: "grist-core"
           - name: "grist"
             repo: "grist-ee"
+          # For now, we build it twice, with `grist-ee` being a
+          # backwards-compatible synoym for `grist`.
           - name: "grist-ee"
             repo: "grist-ee"
     steps:

README.md

@@ -83,7 +83,8 @@ If you just want a quick demo of Grist:
   * Or you can see a fully in-browser build of Grist at [gristlabs.github.io/grist-static](https://gristlabs.github.io/grist-static/).
   * Or you can download Grist as a desktop app from [github.com/gristlabs/grist-desktop](https://github.com/gristlabs/grist-desktop).
 
-To get `grist-core` running on your computer with [Docker](https://www.docker.com/get-started), do:
+To get the default version of `grist-core` running on your computer
+with [Docker](https://www.docker.com/get-started), do:
 
 ```sh
 docker pull gristlabs/grist
@@ -117,6 +118,22 @@ You can find a lot more about configuring Grist, setting up authentication,
 and running it on a public server in our
 [Self-Managed Grist](https://support.getgrist.com/self-managed/) handbook.
 
+## Available Docker images
+
+The default Docker image is `gristlabs/grist`. This contains all of
+the standard Grist functionality, as well as extra source-available
+code for enterprise customers taken from the the
+[grist-ee](https://github.com/gristlabs/grist-ee) repository. This
+extra code is not under a free or open source license. By default,
+however, the code from the `grist-ee` repository is completely inert and
+inactive. This code becomes active only when an administrator enables
+it by setting either `GRIST_ACTIVATION` or `GRIST_ACTIVATION_FILE`.
+
+If you would rather use an image that contains exclusively free and
+open source code, the `gristlabs/grist-oss` Docker image is available
+for this purpose. It is by default functionally equivalent to the
+`gristlabs/grist` image.
+
 ## The administrator panel
 
 You can turn on a special admininistrator panel to inspect the status