Add snippets for ML Kit Prompt API

[calren]

No description provided.

[snippet-bot]

Here is the summary of changes.

You are about to add 3 region tags.

• ai/src/main/java/com/example/snippets/ai/MLKitPromptAPISnippets.kt:29, tag android_snippets_mlkit_instantiate_model
• ai/src/main/java/com/example/snippets/ai/MLKitPromptAPISnippets.kt:39, tag android_snippets_structured_output_before
• ai/src/main/java/com/example/snippets/ai/MLKitPromptAPISnippets.kt:50, tag android_snippets_structured_output_after

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[ksemenova]

LGTM