Adds code for Wear custom rotary implementation

[kul3r4]

Adds code for Wear custom rotary implementation, improves current code as it does not compile

[snippet-bot]

Here is the summary of changes.

You are about to add 2 region tags.

• wear/src/main/java/com/example/wear/snippets/m3/rotary/Rotary.kt:226, tag android_wear_rotary_custom_ui
• wear/src/main/java/com/example/wear/snippets/m3/rotary/Rotary.kt:250, tag android_wear_rotary_custom_model

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