docs: document the justfile (#91)

* docs: document the justfile

Bless you copilot. 🗡️

* Update README.md

Co-authored-by: Tulip Blossom <tulilirockz@proton.me>

---------

Co-authored-by: Tulip Blossom <tulilirockz@proton.me>

1 files changed, 145 insertions, 0 deletions

diff --git a/README.md b/README.md
index e79c500..0f50ffa 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,151 @@ This template provides an out of the box workflow for getting an ISO image for y
 
 This template provides a way to upload the ISO that is generated from the workflow to a S3 bucket or it will be available as an artifact from the job. To upload to S3 we use a tool called [rclone](https://rclone.org/) which is able to use [many S3 providers](https://rclone.org/s3/). For more details on how to configure this see the details [below](#build-isoyml).
 
+### Justfile Documentation
+
+This `Justfile` contains various commands and configurations for building and managing container images and virtual machine images using Podman and other utilities.
+
+#### Environment Variables
+
+- `repo_organization`: The GitHub repository owner (default: "yourname").
+- `image_name`: The name of the image (default: "yourimage").
+- `centos_version`: The CentOS version (default: "stream10").
+- `fedora_version`: The Fedora version (default: "41").
+- `default_tag`: The default tag for the image (default: "latest").
+- `bib_image`: The Bootc Image Builder (BIB) image (default: "quay.io/centos-bootc/bootc-image-builder:latest").
+
+#### Aliases
+
+- `build-vm`: Alias for `build-qcow2`.
+- `rebuild-vm`: Alias for `rebuild-qcow2`.
+- `run-vm`: Alias for `run-vm-qcow2`.
+
+
+#### Commands
+
+###### `check`
+
+Checks the syntax of all `.just` files and the `Justfile`.
+
+###### `fix`
+
+Fixes the syntax of all `.just` files and the `Justfile`.
+
+###### `clean`
+
+Cleans the repository by removing build artifacts.
+
+##### Build Commands
+
+###### `build`
+
+Builds a container image using Podman.
+
+```bash
+just build $target_image $tag $dx $hwe $gdx
+```
+
+Arguments:
+- `$target_image`: The tag you want to apply to the image (default: aurora).
+- `$tag`: The tag for the image (default: lts).
+- `$dx`: Enable DX (default: "0").
+- `$hwe`: Enable HWE (default: "0").
+- `$gdx`: Enable GDX (default: "0").
+
+##### Building Virtual Machines and ISOs
+
+###### `build-qcow2`
+
+Builds a QCOW2 virtual machine image.
+
+```bash
+just build-qcow2 $target_image $tag
+```
+
+###### `build-raw`
+
+Builds a RAW virtual machine image.
+
+```bash
+just build-raw $target_image $tag
+```
+
+###### `build-iso`
+
+Builds an ISO virtual machine image.
+
+```bash
+just build-iso $target_image $tag
+```
+
+###### `rebuild-qcow2`
+
+Rebuilds a QCOW2 virtual machine image.
+
+```bash
+just rebuild-qcow2 $target_image $tag
+```
+
+###### `rebuild-raw`
+
+Rebuilds a RAW virtual machine image.
+
+```bash
+just rebuild-raw $target_image $tag
+```
+
+###### `rebuild-iso`
+
+Rebuilds an ISO virtual machine image.
+
+```bash
+just rebuild-iso $target_image $tag
+```
+
+##### Run Virtual Machines
+
+###### `run-vm-qcow2`
+
+Runs a virtual machine from a QCOW2 image.
+
+```bash
+just run-vm-qcow2 $target_image $tag
+```
+
+###### `run-vm-raw`
+
+Runs a virtual machine from a RAW image.
+
+```bash
+just run-vm-raw $target_image $tag
+```
+
+###### `run-vm-iso`
+
+Runs a virtual machine from an ISO.
+
+```bash
+just run-vm-iso $target_image $tag
+```
+
+###### `spawn-vm`
+
+Runs a virtual machine using systemd-vmspawn.
+
+```bash
+just spawn-vm rebuild="0" type="qcow2" ram="6G"
+```
+
+##### Lint and Format
+
+###### `lint`
+
+Runs shell check on all Bash scripts.
+
+###### `format`
+
+Runs shfmt on all Bash scripts.
+
 ## Workflows
 
 ### build.yml