docs: add new package release process (#1734)

* add docs

* Add flutter example step

* Add analyze info

* Update

* Update new-package-release-checklist.md

Author: buenaflor

docs/new-package-release-checklist.md

@@ -0,0 +1,57 @@
+# New Package Release Checklist
+
+This page serves as a checklist of what to do when releasing a new package for the first time.
+
+## Release Preparation
+
+- [ ] Make sure the project is set up
+    - [ ] The package only exports the public API
+    - [ ] The package contains an example folder
+    - [ ] The package contains a README.md file
+        - [ ] CI badges show a status
+    - [ ] The package contains a CHANGELOG.md file (symlink to the root changelog)
+    - [ ] The package contains a dartdoc_options.yaml file (symlink to the root file)
+    - [ ] The package contains a LICENSE (default is `MIT`)
+    - [ ] The package contains a pubspec.yaml file
+    - [ ] The package contains a analysis_options.yaml file
+
+- [ ] Update the [Flutter example](https://github.com/getsentry/sentry-dart/tree/main/flutter/example) to use your new package if applicable
+
+- [ ] Make sure your new package has a `version.dart` in the `lib/src` folder.
+    - This is used to set the version and package in the `Hub`. See this [example](https://github.com/getsentry/sentry-dart/blob/8609bd8dd7ea572e5d241a59643c7570e5621bda/sqflite/lib/src/sentry_database.dart#L69).
+    - The version will be updated to the newest version after triggering the release process.
+
+- [ ] Create a new workflow called `your-package-name.yml` for building and testing the package.
+
+- [ ] Excluding `your-package-name.yml`, add the package to the `paths-ignore` section of all package workflow files.
+  - For examples see `sqflite.yml`, `dio.yml` etc...
+     
+- [ ] Add an entry to [diagram.yml](https://github.com/getsentry/sentry-dart/blob/main/.github/workflows/diagrams.yml) for your package. 
+
+- [ ] In the root `.gitignore` file add the package coverage as ignored.
+
+The `analyze` workflow will fail in your PR and in the main branch because the package is not released yet and the `pubspec.yaml` is not 'valid' according to the analyzer.
+This is expected - it will succeed after the release.
+- [ ] Make sure the analyze workflow doesn't have other failures, only the one mentioned above.
+
+- [ ] **Very important**: add your package to `scripts/bump-version.sh`.
+
+## Doing the Release
+
+Do these steps in the **correct order**
+
+- [ ] Add your package only as a `pub-dev` target in `.craft.yml`. (**not registry**)
+  - The release process might fail if you add it to the registry at this point.
+- [ ] Trigger the release
+  - [ ] Check that the release bot successfully updated the versions in `version.dart` and `pubspec.yaml` in the release branch.
+
+## After the first release
+
+- [ ] Check if package is succesfully released on `pub.dev`
+- [ ] Add the package to the Sentry Release Registry 
+  - Instructions on how to do this can be found [here](https://github.com/getsentry/sentry-release-registry#adding-new-sdks)
+  - [Example PR](https://github.com/getsentry/sentry-release-registry/pull/136)
+- [ ] Add an entry to `.craft.yml` for the package in the `registry` section.
+  - Now all future releases will be added to the registry automatically.
+- [ ] Update the repo's `README.md`
+- [ ] Prepare and merge [Sentry documentation](https://github.com/getsentry/sentry-docs/)