Add custom prompt, with game title tie in.

Put the custom initial prompt in our config, additionally we should get the games name either from the initial prompt or maybe more appropriately through the actual window title.

No files or tests are named. Start by locating the configuration handling and the entry point that sends images to Ollama, then inspect how the active window title can be read. Done means a configurable initial prompt is used and the game title is consistently incorporated, with the chosen title source documented by the implementation.

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