docs: add tools container runbook

docs/installation/production/configuration.md

@@ -1,6 +1,6 @@
 # Configuration
 
-Open the tools container, which includes all the tools needed:
+Open the [tools container](../../runbooks/tools-container.md), which includes all the tools needed:
 
 === "Docker"
 

docs/runbooks/tools-container.md

@@ -0,0 +1,36 @@
+# Tools container
+
+The tools container makes it easy to get all of the dependencies needed to interact with the homelab.
+
+## How to open it
+
+You can use the default Docker wrapper, or use Nix if you have Nix installed
+
+=== "Docker"
+
+    ```sh
+    make tools
+    ```
+
+=== "Nix"
+
+    ```sh
+    nix-shell
+    ```
+
+It will open a shell like this:
+
+```
+[nix-shell:/home/khuedoan/Documents/homelab]# echo hello
+hello
+```
+
+## How it works
+
+- All dependencies are defined in `./shell.nix`
+- When you run `make tools`, it will run a thin Docker wrapper with the `nixos/nix` image (because not everyone has Nix installed) and mount some required volumes
+- `nix-shell` will start an interactive shell based on the Nix expression in `./shell.nix` and install everything from there
+
+## Known issues
+
+- If your Docker engine is not running in rootless mode, all files created by the tools container will be owned by `root`

mkdocs.yml

@@ -64,6 +64,7 @@ nav:
     - runbooks/documentation.md
     - runbooks/gitea.md
     - runbooks/longhorn.md
+    - runbooks/tools-container.md
     - runbooks/vault.md
   - troubleshooting.md
   - User guide: