doc: add release process notes

Author: fry69

RELEASE.md

@@ -0,0 +1,30 @@
+## Release process
+
+### Version update
+
+Update version string in
+
+- `package.json` - `"version"` property value
+- `files-to-prompt.ts` - `VERSION` variable at the top of the script
+- `README.md` - download links for the raw script in the `Installation` section
+
+### Changelog
+
+Generate [CHANGELOG.md](https://github.com/fry69/files-to-prompt-ts/blob/main/CHANGELOG.md) from git tag annotations with this commandline:
+
+```shell
+git for-each-ref --sort=-taggerdate --format='## %(refname:short)%n%(contents)%n---%n' refs/tags | sed 's/%n/\n/g' > CHANGELOG.md
+```
+
+### jsr.io
+
+- `jsr.json` - `"version"` property value
+
+> **Note:** Updating this version string will trigger the [publish.yml](https://github.com/fry69/files-to-prompt-ts/blob/main/.github/workflows/publish.yml) workflow and upload the repository to `jsr.io` on push to GitHub
+
+### General Notes
+
+- minified build will be generated by [build.yml](https://github.com/fry69/files-to-prompt-ts/blob/main/.github/workflows/build.yml) workflow after **release**
+- test output will be generated and inserted into `README.md` by [test.yml](https://github.com/fry69/files-to-prompt-ts/blob/main/.github/workflows/test.yml) after **tagging**
+- `test.yml` workflow can fail (`bun test` reports failed tests), pay attention to GitHub notifications
+