Add example NFC mapping files

videos/key_mapping.txt

@@ -0,0 +1,24 @@
+# NFC Key Mapping File for Single Video Files
+# Format: NFC_ID, Movie_Name
+# These map to individual files in the 'specific' folder
+#
+# Instructions:
+# 1. Each line maps an NFC tag to a single video file
+# 2. NFC_ID is the unique identifier from your NFC card/tag
+# 3. Movie_Name should match the filename (without extension) in videos/specific/
+# 4. Lines starting with # are comments and will be ignored
+#
+# Examples:
+# 12345678,avengers
+# 87654321,spider-man
+# 11223344,iron-man
+# 99887766,guardians-galaxy
+#
+# Tips:
+# - Keep movie names simple (no special characters)
+# - Names are case-insensitive
+# - The system will find .mp4, .avi, .mkv, etc. automatically
+# - For folder sequences, use folder_mapping.txt instead!
+#
+# Your mappings below:
+