API keys for OpenAI, Anthropic, Google, and Perplexity now live in
app.secretStorage rather than the unencrypted plugin data file.
loadSettings runs a one-shot migration that copies any pre-existing
*ApiKey values into SecretStorage and strips them from saved data, so
upgrading users keep their keys without leaving an unencrypted copy
behind. Bumps minAppVersion to 1.11.4 (required by SecretStorage) and
the obsidian devDep to match. Addresses the plugin reviewer feedback
on PR obsidianmd/obsidian-releases#6690.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>