refactor: Add more checks to pre-commit

Updated existing pre-commit hooks and added some new hooks:

- Remove trailing whitespace
- Ensure every non-empty file ends with a new line
- Check YAML file validity
- Prevent adding large files
- Ensure any scripts with shebangs are executable

Added a GitHub action to run pre-commit on every commit. Removed any
existing actions which duplicate pre-commit.

Ran pre-commit on the codebase.

app/boards/shields/leeloo/Kconfig.defconfig

@@ -8,7 +8,7 @@ config ZMK_KEYBOARD_NAME
 
 config ZMK_SPLIT_ROLE_CENTRAL
 	default y
-	
+
 endif
 
 if SHIELD_LEELOO_LEFT || SHIELD_LEELOO_RIGHT

app/boards/shields/leeloo/README.md

@@ -6,20 +6,22 @@ Keyboard Designer: [clicketysplit.ca](https://clicketysplit.ca)
 GitHub: [ClicketySplit](https://github.com/ClicketySplit)
 Hardware Supported: Pro Micro, Elite-C, nice!nano v2
 
-Albeit, there is no doubt where Leeloo's heritage is derived from—Lily58, and Corne.  It is not a copy-paste-modify implementation.
+Albeit, there is no doubt where Leeloo's heritage is derived from—Lily58, and Corne. It is not a copy-paste-modify implementation.
 
 Leeloo has been designed from scratch; everything from the schematic to its PCB footprints, and column stagger. There are some subtle differences that may not be apparent; however, its subtle changes enable an interesting future.
 
 Features:
-* 4x6x5m Split Keyboard
-* Support for MX/Box or Low Profile Choc switches.
-* 90% of the switches are socketed; with the exception to the rotary encoder positions—6 positions require soldering.
-* Support for 128x32 OLED Displays.
-* The option to select one of three positions for an EC11 rotary encoder on each half.
-* Support for Alps Alpine Micro Switch
-* Support for 3.7v 301230 LiPo Battery
+
+- 4x6x5m Split Keyboard
+- Support for MX/Box or Low Profile Choc switches.
+- 90% of the switches are socketed; with the exception to the rotary encoder positions—6 positions require soldering.
+- Support for 128x32 OLED Displays.
+- The option to select one of three positions for an EC11 rotary encoder on each half.
+- Support for Alps Alpine Micro Switch
+- Support for 3.7v 301230 LiPo Battery
 
 # Building Your Firmware
+
 ZMK Firmware: [Introduction to ZMK](https://zmk.dev/docs/)
 Installation: [Installing ZMK](https://zmk.dev/docs/user-setup)
 Customization: [Customizing ZMK](https://zmk.dev/docs/customization)
@@ -36,6 +38,7 @@ Build command for your custom keymap of Leeloo:
     west build -d build/left -p -b nice_nano_v2 -- -DSHIELD=leeloo_left -DZMK_CONFIG="C:/dev/zmk/[yourName]/leeloo/config"
 
 # Support
+
 If you have any questions with regards to Leeloo, please [Contact Us](https://clicketysplit.ca/pages/contact-us).
 
 Clickety Split