feat(website): update superfile-config.mdx for Fish shell setup (#1142)

Added instructions for configuring Fish shell.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Documentation**
  * Renamed MacOS/Linux heading to indicate support for Bash or Fish.
* Added Fish shell-specific setup and cd_on_quit guidance, including how
to add and reload Fish configuration and reference to Fish docs.
* Retained Bash guidance for updating and reloading Bash configuration.
  * Windows instructions left unchanged.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: wleoncio

website/src/content/docs/configure/superfile-config.mdx

@@ -46,7 +46,9 @@ The editor your directories will be opened with (Leave blank to use defaults : `
 
 After setting to `true`, you need to update your shell config file. Sample changes :
 
-##### MacOS/Linux (bash)
+##### MacOS/Linux (bash or fish)
+
+###### Bash
 
 Open the file:
 
@@ -64,6 +66,26 @@ Save, exit, and reload your `.bashrc` file:
 source ~/.bashrc
 ```
 
+###### Fish
+
+Open the file:
+
+```bash
+$EDITOR ~/.config/fish/config.fish
+```
+
+If you suspect your `config.fish` file is located somewhere else, read [the Fish shell documentation](https://fishshell.com/docs/current/language.html#configuration)
+
+Copy the following code into the file:
+
+<CodeBlock file="cd_on_quit/cd_on_quit.fish" />
+
+Save, exit, and reload `config.fish`:
+
+```bash
+source ~/.config/fish/config.fish
+```
+
 ##### Windows (Powershell)
 
 Open the file: