feat!: v4 release (#871)

Any advanced configuration should be done via a
release-please-config.json.

Fixes #859
Fixes #858
Fixes #857
Fixes #852

feat!: remove most configuration options in favor of manifest
configuration to configure the release-please-action
refactor!: rewrite in typescript
feat!: remove command option in favor of setting `release-type` and
`skip-github-release`/`skip-github-pull-request`
feat!: run on node20
deps!: upgrade release-please to v16

.eslintignore

@@ -0,0 +1,8 @@
+**/node_modules
+**/coverage
+test/fixtures
+build/
+docs/
+protos/
+samples/generated/
+dist/