Add detailed log view

Discussed on the dev call, we may want to investigate the behavior of new features and clients from the app itself. The Breez app had a similar feature where a simple tab opened a log file. I think it would be nice to do the same here and write events out to something like `debug.log` which may be opened in the settings page.

The issue names no files, tests, or entry points. Start by locating the settings page and the app's current event handling, then clarify the log format, storage, and viewing behavior for debug.log. Done means the app records relevant events and exposes the detailed log from settings.

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