feat(internal/gensnippets): add license header and region tags

[tbpg]

No description provided.

[snippet-bot]

Here is the summary of possible violations 😱

There is a possible violation for not having product prefix.

• internal/gensnippets/main.go:166, tag %v

The end of the violation section. All the stuff below is FYI purposes only.

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Here is the summary of changes.

You are about to add 1 region tag.

• internal/gensnippets/main.go:166, tag %v

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