Gupshup - new components

[michelle0927]

Resolves #13232

Summary by CodeRabbit

• New Features

  • Send Gupshup template messages with parameter support.
  • Update Gupshup subscription configurations.
  • Template selector: fetch and choose available template IDs when composing messages.

• Refactor

  • Improved Gupshup integration internals for more reliable message sending and subscription updates.

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