Show Autocomplete suggestions automatically

Many text editors show autocomplete suggestions automatically, without requiring a keyboard command to trigger. It would be nice if Postico allowed that too.

However, before we can implement this, we need to make autocomplete a bit more context sensitive, otherwise suggestions are likely to be more annoying than useful...

The issue mentions no files, tests, or entry points to inspect. First clarify what context-sensitive autocomplete should cover and how automatic suggestions should be triggered; define the expected behavior and acceptance criteria before locating the relevant implementation.

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