doc: text editor/IDE configuration

Add the guidance on how to configure the text editor/IDE to get direct
style/linter/type checker feedback while coding.

Signed-off-by: Gaëtan Lehmann <gaetan.lehmann@vates.tech>

Author: glehmann

README.md

@@ -366,7 +366,78 @@ ruff check lib/ tests/
 flake8
 ```
 
-The code checker diagnostics can also be shown directly in your IDE or text editor.
+The code checker diagnostics can also be shown directly in your IDE or text editor, by using plugins or language
+servers (LSP).
+
+### Visual Studio Code
+
+A few plugins are recommended to properly report the diagnostics during the development:
+* [BasedPyright](https://marketplace.visualstudio.com/items?itemName=detachhead.basedpyright)
+* [cornflakes-linter](https://marketplace.visualstudio.com/items?itemName=kevinglasson.cornflakes-linter)
+* [ruff](https://marketplace.visualstudio.com/items?itemName=charliermarsh.ruff)
+
+If you want the coding style warning to appear as you type, set the option
+`Extensions` > `cornflakes-linter` > `Cornflakes > linter: Run` to `onType`.
+
+~~~json
+{
+    "cornflakes.linter.run": "onType"
+}
+~~~
+
+### Helix
+
+Install the required language servers:
+* basedpyright with `uv tool install basedpyright`
+* pylsp with `uv tool install python-lsp-server[flake8] --with pylsp-rope`.
+
+`ruff`, which is also used as a language server, is already installed as a dev dependency.
+
+Create a `.helix/language.toml` in the project. Make sure to exclude it in git,
+either in your user configuration (`~/.config/git/ignore`) or in the project
+configuration (`.git/info/exclude`).
+
+~~~toml
+[[language]]
+name = "python"
+language-servers = [
+  "basedpyright",
+  "pylsp",
+  "ruff",
+]
+auto-format = false
+
+[language-server.basedpyright.config.basedpyright.analysis]
+diagnosticMode = "workspace"
+
+[language-server.pylsp.config.pylsp.plugins]
+autopep8.enabled = false
+flake8.enabled = true
+jedi.enabled = false
+mccabe.enabled = false
+preload.enabled = false
+pycodestyle.enabled = false
+pydocstyle.enabled = false
+pyflakes.enabled = false
+pylint.enabled = false
+yapf.enabled = false
+~~~
+
+### Other LSP-Compatible Editors
+
+Most modern editors use the Language Server Protocol (LSP) to enhance
+functionality. The following servers are generally suggested for this project:
+
+* basedpyright: Real-time type checking ('uv tool install basedpyright').
+* pylsp: Coding style feedback via flake8 (`uv tool install "python-lsp-server[flake8]"`).
+* ruff: Immediate linting (included as a dev dependency).
+
+Configuration is highly editor-specific; please consult your editor's
+documentation. Contributions to these docs via PR are always welcome!
+
+### Others
+
+Please add your configuration hints here!
 
 ## VM setup
 Many tests expect VMs with: