Contribution guidelines rework

packages/mermaid/src/docs/community/contributing.md

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+
+---
+
+# Old Contributing Guide
+
+Please read in detail about how to contribute documentation and code on the [Mermaid documentation site.](https://mermaid-js.github.io/mermaid/#/development)
+
+---
+
+# Mermaid contribution cheat-sheet
+
+## Requirements
+
+- [volta](https://volta.sh/) to manage node versions.
+- [Node.js](https://nodejs.org/en/). `volta install node`
+- [pnpm](https://pnpm.io/) package manager. `volta install pnpm`
+
+## Development Installation
+
+If you don't have direct access to push to mermaid repositories, make a fork first. Then clone. Or clone directly from mermaid-js:
+
+```bash
+git clone git@github.com:mermaid-js/mermaid.git
+cd mermaid
+```
+
+Install required packages:
+
+```bash
+# npx is required for first install as volta support for pnpm is not added yet.
+npx pnpm install
+pnpm test # run unit tests
+pnpm dev # starts a dev server
+```
+
+Open <http://localhost:9000> in your browser after starting the dev server.
+You can also duplicate the `example.html` file in `demos/dev`, rename it and add your own mermaid code to it.
+That will be served at <http://localhost:9000/dev/your-file-name.html>.
+
+### Docker
+
+If you are using docker and docker-compose, you have self-documented `run` bash script, which is a convenient alias for docker-compose commands:
+
+```bash
+./run install # npx pnpm install
+./run test # pnpm test
+```
+
+## Testing
+
+```bash
+# Run unit test
+pnpm test
+# Run unit test in watch mode
+pnpm test:watch
+# Run E2E test
+pnpm e2e
+# Debug E2E tests
+pnpm dev
+pnpm cypress:open # in another terminal
+```
+
+## Branch name format:
+
+```text
+   [feature | bug | chore | docs]/[issue number]_[short description using dashes ('-') or underscores ('_') instead of spaces]
+```
+
+eg: `feature/2945_state-diagram-new-arrow-florbs`, `bug/1123_fix_random_ugly_red_text`
+
+## Documentation
+
+Documentation is necessary for all non bugfix/refactoring changes.
+
+Only make changes to files that are in [`/packages/mermaid/src/docs`](packages/mermaid/src/docs)
+
+**_DO NOT CHANGE FILES IN `/docs` MANUALLY_**
+
+The `/docs` folder will be rebuilt and committed as part of a pre-commit hook.
+
+[Join our slack community if you want closer contact!](https://join.slack.com/t/mermaid-talk/shared_invite/enQtNzc4NDIyNzk4OTAyLWVhYjQxOTI2OTg4YmE1ZmJkY2Y4MTU3ODliYmIwOTY3NDJlYjA0YjIyZTdkMDMyZTUwOGI0NjEzYmEwODcwOTE)