chore: add marimo editable install in pixi env, simplify docs in CONTRIBUTING.md

CONTRIBUTING.md

@@ -30,13 +30,7 @@ Install [pixi](https://github.com/prefix-dev/pixi) to manage your development en
 > Note that developing in Gitpod is not officially supported by the marimo team.
 
 ```bash
-pixi run hatch shell
-```
-
-Now you can install the environment frontend and Python dependencies.
-
-```bash
-make fe && make py
+pixi shell
 ```
 
 After doing this, you can instantiate your marimo development environment by running the following command.
@@ -45,10 +39,12 @@ After doing this, you can instantiate your marimo development environment by run
 make dev
 ```
 
+This will launch two processes, the backend one in port 2718 and the front end one in port 3000.
+
 You can optionally install [pre-commit](https://pre-commit.com/) hooks to automatically run the validation checks when making a commit:
 
 ```bash
-uvx pre-commit install
+pixi run pre-commit install
 ```
 
 To build the frontend unminified, run:

pyproject.toml

@@ -579,3 +579,6 @@ pre_commit = ">=4.2.0,<5"
 uv = ">=0.6.12,<0.7"
 python = "3.12.*"
 pip = ">=25.0.1,<26"
+
+[tool.pixi.pypi-dependencies]
+marimo = {path = ".", editable = true}