docs: Add a how-to for publishing an app's snap

Makefile

@@ -86,7 +86,7 @@ docs:  ## Build documentation
 
 .PHONY: docs-auto
 docs-auto:  ## Build and host docs with sphinx-autobuild
-	uv run --group docs sphinx-autobuild -b dirhtml --open-browser --port=8080 --watch $(PROJECT) -W $(DOCS) $(DOCS_OUTPUT)
+	uv run --group docs sphinx-autobuild -b dirhtml --open-browser --port=8080 -W $(DOCS) $(DOCS_OUTPUT)
 
 # Below are intermediate targets for setup. They are not included in help as they should
 # not be used independently.

docs/conf.py

@@ -81,6 +81,11 @@
 
 # region Options for extensions
 
+intersphinx_mapping = {
+    "launchpad": ("https://documentation.ubuntu.com/launchpad", None),
+    "ubuntu": ("https://documentation.ubuntu.com/project", None),
+}
+
 # Client-side page redirects.
 rediraffe_redirects = "redirects.txt"
 

docs/how-to/index.rst

@@ -13,3 +13,4 @@ These pages walk you through the manual processes and workflows in the Starcraft
 
     starcraft-style-guide
     add-a-page-meta-description
+    publish-a-snap

docs/how-to/publish-a-snap.rst

@@ -0,0 +1,64 @@
+.. meta::
+    :description: How to publish a Starcraft app as a snap in the snap store.
+
+
+.. _how-to-publish-a-starcraft-snap:
+
+Publish a Starcraft snap
+========================
+
+Craft apps are packed into snaps and published to the Snap Store according to
+the process in this guide. Our process doesn't apply to other apps or snaps
+maintained by other teams.
+
+We build our snaps on Launchpad with
+:external+launchpad:ref:`snap recipes <build-snaps-in-launchpad>`. Each snap must have
+three channels for the latest revisions:
+
+- ``latest/edge``
+- ``latest/candidate``
+- ``latest/stable``
+
+Once a craft app reaches version 2.0, there should be a track representing each
+supported major release.
+
+Initialize the project on Launchpad
+-----------------------------------
+
+If the app is new, you must register and sync it on Launchpad before you can
+publish it.
+
+First, `register the project <https://launchpad.net/projects/+new>`__. Make
+`~canonical-starcraft <https://launchpad.net/~canonical-starcraft>`__ both the
+maintainer and the driver.
+
+Next, set the project to import from the source on GitHub.
+
+If successful, https://code.launchpad.net/<yourcraft> should open the imported Git 
+repository. If it isn't working, compare your project to the settings and
+results in https://code.launchpad.net/snapcraft.
+
+Register the snap
+-----------------
+
+If the snap is not yet registered, run ``snapcraft register <craft-name>`` in a terminal
+to register it. When creating the recipe for the candidate channel, contact the store
+team to have Canonical take ownership.
+
+Publish to ``latest/edge``
+--------------------------
+
+The ``main`` branch of all craft apps should publish to the ``latest/edge``
+channel. This is typically the first recipe that you create.
+
+Go to the project page on Launchpad and click **Create snap package**. Name the recipe
+**<yourcraft>-edge** and give the Starcraft team ownership of it.
+
+Select the main branch of the app's repository and check all relevant processors for
+your app. In most cases, this will be the :external+ubuntu:ref:`supported architectures
+<supported-architectures>` for the latest Ubuntu LTS, or a subset of it.
+
+Select **Automatically build when branch changes** and **Automatically upload to store**,
+and enter the snap name. Leave the track empty and select the **Edge** risk.
+
+After saving, test that the builds work correctly by manually requesting a build.