Add horizontal pager

[kul3r4]

Add horizontal pager snippet so that it can be used in https://developer.android.com/training/wearables/compose/migrate-to-material3.mdd

[snippet-bot]

Here is the summary of changes.

You are about to add 1 region tag.

• wear/src/main/java/com/example/wear/snippets/m3/pager/Pager.kt:37, tag android_wear_horizontal_pager

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