v0.9.4

• Security fixes for the conversion server and the app: only book formats are converted, Calibre runs sandboxed, uploads are size-checked, stored tokens are encrypted, and imported file names are sanitized
• Turning the conversion server off now stops any upload in progress
• Books saved from the Kindle keep their covers
• Google Books lookups have their own setting (Settings > Book details)

What's Changed

• Security: only convert allowlisted input formats by @spandan-kumar in #12
• Security: sandbox Calibre, timeouts, generic errors, upload limits by @spandan-kumar in #13
• Security: app-side audit fixes by @spandan-kumar in #14
• Google Books default as its own flag; server in the F-Droid build by @spandan-kumar in #11
• Fix PDF output under the Calibre sandbox by @spandan-kumar in #16
• Covers for books saved from the Kindle by @spandan-kumar in #15

Full Changelog: v0.9.3...v0.9.4