Implement an Interactive UI

* **What:** Build the application as an interactive Terminal User Interface (TUI) using the `Bubble Tea` library.
* **Why:** This will create a much more engaging and user-friendly experience.
* **How:**
1. Integrate the `Bubble Tea` library.
2. Create a model that holds the application state.
3. The initial view could be a menu with options like "Fetch All Pokémon" and "Find Pokémon by Name/Number".

The issue does not name files, tests, or an entry point. Start by reviewing the existing Go CLI and its fetch and search flows; done means integrating Bubble Tea, adding application state, and providing menu options for fetching all Pokémon and finding one by name or number.

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