Use mprocs by default with start-airflow

Dockerfile.ci

@@ -1244,7 +1244,7 @@ function environment_initialization() {
         fi
         export AIRFLOW__CORE__LOAD_EXAMPLES=${LOAD_EXAMPLES}
         wait_for_asset_compilation
-        if [[ ${USE_MPROCS:="false"} == "true" || ${USE_MPROCS} == "True" ]]; then
+        if [[ ${TERMINAL_MULTIPLEXER:="mprocs"} == "mprocs" ]]; then
             # shellcheck source=scripts/in_container/bin/run_mprocs
             exec run_mprocs
         else

contributing-docs/03_contributors_quick_start.rst

@@ -644,15 +644,37 @@ If ``breeze`` was started with ``breeze --python 3.10 --backend postgres`` (or s
 .. note::
     ``stop_airflow`` is available only when ``breeze`` is started with ``breeze start-airflow``.
 
-Using mprocs Instead of tmux
+Using tmux Instead of mprocs
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-By default, ``breeze start-airflow`` uses tmux to manage Airflow components. You can use mprocs as an
-alternative with the ``--use-mprocs`` flag:
+By default, ``breeze start-airflow`` uses mprocs to manage Airflow components. You can use ``tmux`` as an
+alternative with the ``--terminal-multiplexer tmux`` argument. The last choice of yours will be remembered
+for the next run, you can switch back to ``mprocs`` anytime by using ``--terminal-multiplexer mprocs``.
 
 .. code-block:: bash
 
-  breeze start-airflow --use-mprocs
+  breeze start-airflow --terminal-multiplexer tmux
+
+and
+
+.. code-block:: bash
+
+  breeze start-airflow --terminal-multiplexer mprocs
+
+You can also switch terminal multiplexer via breeze config:
+
+.. code-block:: bash
+
+  breeze setup config --terminal_multiplexer tmux
+  breeze setup config --terminal_multiplexer mprocs
+
+** Benefits of using tmux:**
+
+* Familiar terminal multiplexer for many developers
+* More control over panes and windows
+* Customizable key bindings and layouts
+* Wide range of plugins and extensions
+* ability to see more than one log at a time
 
 **Benefits of using mprocs:**
 
@@ -670,7 +692,6 @@ For more information on mprocs, look at `mprocs documentation <mprocs/MPROCS_QUI
 
    breeze --help
 
-
 Following are some of important topics of `Breeze documentation <../dev/breeze/doc/README.rst>`__:
 
 * `Breeze Installation <../dev/breeze/doc/01_installation.rst>`__

contributing-docs/mprocs/MPROCS_QUICK_REFERENCE.md

@@ -21,24 +21,41 @@
 
 ## Basic Command
 
+Start airflow uses mprocs by default:
+
+```bash
+breeze start-airflow
+```
+
+You can switch to using `tmux` instead by specifying the option:
+
 ```bash
-breeze start-airflow --use-mprocs
+breeze start-airflow --terminal-multiplexer tmux
 ```
 
-Breeze will start Airflow components using mprocs to manage multiple processes in a single terminal window.
+Once you select the terminal multiplexer, Breeze will remember your choice for future runs.
+
+You can also switch terminal multiplexers by running `breeze setup config`:
+
+```bash
+breeze setup config --terminal-multiplexer mprocs
+breeze setup config --terminal-multiplexer tmux
+```
+
+
+When Breeze will start Airflow components using mprocs to manage multiple processes in a single terminal window.
 It will generate dynamically the required configuration based on the selected executor and options and use it,
 the generated configuration file is stored in a `files` folder inside the container, so that you can also
 use it outside of Breeze if needed.
 
 ## Common Usage Patterns
 
-| Command                                                       | Description                     |
-|---------------------------------------------------------------|---------------------------------|
-| `breeze start-airflow --use-mprocs`                           | Start Airflow with mprocs       |
-| `breeze start-airflow --use-mprocs --debug scheduler`         | Debug scheduler with mprocs     |
-| `breeze start-airflow --use-mprocs --executor CeleryExecutor` | Use mprocs with Celery          |
-| `breeze start-airflow --use-mprocs --dev-mode`                | Use mprocs in dev mode          |
-| `breeze start-airflow --use-tmux`                             | Explicitly use tmux (default)   |
+| Command                                                         | Description                                         |
+|-----------------------------------------------------------------|-----------------------------------------------------|
+| `breeze start-airflow --terminal-multiplexer mprocs`            | Start Airflow with mprocs (and remember the choice) |
+| `breeze start-airflow --terminal-multiplexer tmux`              | Start Airflow with tmux (and remember the choice)   |
+| `breeze start-airflow --debug scheduler`                        | Debug scheduler with last selected multiplexer      |
+| `breeze start-airflow --dev-mode --terminal-multiplexer mprocs` | Use mprocs in dev mode (and remember the choice)    |
 
 
 ## mprocs Keyboard Shortcuts
@@ -67,7 +84,7 @@ use it outside of Breeze if needed.
 
 | Variable                   | Purpose                         |
 |----------------------------|---------------------------------|
-| `USE_MPROCS`               | Enable mprocs mode              |
+| `TERMNAL_MULTIPLEXER`      | Use mprocs when set to "mprocs" |
 | `INTEGRATION_CELERY`       | Enable Celery components        |
 | `CELERY_FLOWER`            | Enable Flower UI                |
 | `STANDALONE_DAG_PROCESSOR` | Enable standalone DAG processor |