[Doc] document the release process (#631)

Author: tdavidcl

doc/mkdocs/docs/devdoc/release_process.md

@@ -0,0 +1,31 @@
+# Release process
+
+Shamrock is released on a 6 months basis. The release process goes as follows.
+
+## Changing the version
+
+We first change the version of the code :
+```cmake
+set(SHAMROCK_VERSION_MAJOR 2024)
+set(SHAMROCK_VERSION_MINOR 10)
+set(SHAMROCK_VERSION_PATCH 0)
+```
+Here the major version is the current year, and the minor version is the current month. Finally, the patch version indicate the minor release (bug fix or other).
+
+## The release branch
+
+First, if this is a true release (opposed to a patch), we branch from `main` and name it `release/<major>.<minor>.x`.
+
+## The release workflow
+
+We launch the `Prepare release` workflow on the release branch. This will generate the doc, the coverage info and the source code archive.
+
+## Creating the release
+
+We then draft a new release on GitHub. The tag must be set to `v<major>.<minor>.<patch>`, and we set the target branch to `release/<major>.<minor>.x`. Then set the release name to `Shamrock <major>.<minor>.<patch>`.
+
+Then generate the release note from the last tag.
+
+For the files, add the documentation, license, and coverage, named `Shamrock-<major>.<minor>.<patch>-<filename>`, except for the license file that will be named `LICENSE`.
+
+Finally, write the text and ... done !

doc/mkdocs/mkdocs.yml

@@ -34,6 +34,7 @@ nav:
   - 'Develloper Doc' :
     - 'Git guide' : 'devdoc/git_guide.md'
     - 'VSCode setup' : 'devdoc/vscode-setup.md'
+    - 'Release process' : 'devdoc/release_process.md'
     - 'Using the logs' : 'devdoc/log_system.md'
     - 'Local LLVM' : 'devdoc/using_local_llvm.md'
     - 'Codebase Organisation' : 'devdoc/codebase_org.md'