RELEASE.md: sketch the release notes

Author: nfrisby

RELEASE.md

@@ -68,12 +68,29 @@ to open them up to the larger community. The release team also meets ad-hoc as n
 
 # Release notes
 
-# Detailed changelog table
+The release notes are drafted and published via the GitHub releases UI.
+Our current template contains the following sections.
+
+- (no header) A very-high level summary of the release.
+  For larger release, it may be best for the Cardano Head of Product to draft this summary instead of the release engineer, since they have more context.
+- Known Issues
+- Technical Specification (usually unchanged)
+- Links to `cardano-node` documentation
+  It seems to be a judgement call whether each of these should specify the upstream version.
+- Changelogs
+   - Summaries of the major dependencies' changelogs.
+     These are written as a few sentences that an interested user and/or dev would find helpful.
+     It may be best for the individual teams to draft these summaries instead of the release engineer, since they have more context.
+   - Links to the individual changelog of each upstream package that IOG maintains.
+     See the script explained below.
+
+## Detailed changelog table
 
 There's a script (`scripts/generate-release-changelog-links.hs`) that generates a table of changelogs for each of the package versions included in a given `cardano-node` release. The script takes a cabal-generated `plan.json` and a GitHub API access token, and outputs a large table which contains links to the `CHANGELOG.md` file (if one exists) for each of the package versions contained in the build plan.
 
 > example usage (be sure to run `cabal build all` at least once beforehand):
 > ```
-> ./scripts/generate-release-changelog-links.hs ./dist-newstyle/cache/build.json $GITHUB_API_TOKEN
+> $ nix build .#project.x86_64-linux.plan-nix.json
+> $ ./scripts/generate-release-changelog-links.hs result-json $GITHUB_API_TOKEN
 > ```
 > for more information, including how to generate / retrieve a GitHub API token, use `./scripts/generate-release-changelog-links.hs --help`