Add new node for Wan Vace Auto Joiner

[Rhovanx]

New Custom Node: Wan Vace Auto Joiner

This PR adds Wan Vace Auto Joiner, a ComfyUI custom node set that enables seamless batch video joining using WAN VACE with Easy-Use For Loop automation.

Key points

• Designed for WAN VACE workflows
• Uses a value1 barrier pattern to prevent premature loop advancement
• Runs VACE exactly N-1 times for N video clips
• No required pip dependencies

Repository:
https://github.com/Rhovanx/wan_vace_auto_joiner

[ltdrdata]

https://github.com/Rhovanx/wan_vace_auto_joiner/blob/80a93fd39756f523fa06d08ba9ae3d5450e14398/wan_vace_auto_joiner.py#L250

https://github.com/Rhovanx/wan_vace_auto_joiner/blob/80a93fd39756f523fa06d08ba9ae3d5450e14398/wan_vace_auto_joiner.py#L504

https://github.com/Rhovanx/wan_vace_auto_joiner/blob/80a93fd39756f523fa06d08ba9ae3d5450e14398/wan_vace_auto_joiner.py#L578

directory and file_prefix shoulde be sanitized. And the joined path must be isolated to a restricted directory.

[Rhovanx]

Updated! Added input sanitization and path validation:

sanitize_prefix() removes path separators and dangerous characters
validate_directory() verifies and resolves directory paths
validate_path_within_directory() prevents path traversal attacks

All file operations now stay within the user-specified directory.