[maelchiotti]

Closes #588.

Changes

Export frequency of 3 days (268fd93)

settings_auto_export_frequency_value had no 3 case, although 3 days is a slider value (automaticExportFrequenciesValues). The tile showed "Every " with nothing after it. Adds 3{3 days} to app_en.arb. The other languages get it from Crowdin and keep their other case until then.

Migrations in a single transaction (cd8d8ab)

The migrations to v2 and v3 removed the notes, then put them back, in separate transactions. The clear() of v2 even ran outside of any transaction. Each migration now:

1. reads the notes and their labels;
2. in one writeTxn, removes the old notes, puts the migrated ones and links their labels (_putLabels, same steps as NotesService.putAllLabels, which can't be called inside another transaction).

The v3 migration changes each note's id, and so the isarId its label links are stored under: the links were lost. They are now read before and linked again after.

This only matters for users updating from very old versions. Not tested on a database of those versions.

Title sort (2ac356e)

Note.compareTo now compares title.toLowerCase(), like the labels. Users with mixed-case titles will see a different order: worth a line in the CHANGELOG at release time.

Dead code (8e0fdde, 8bc86fe)

• Removes PreferenceKey.preferenceSecure. It always threw an ArgumentError (get on a secure key) and was never used.
• Removes NotesService.putAllLabels, unused since [584] Fix partial backup restore #585 (merged here with 06dc314) and the migration change above.

Checks

• flutter gen-l10n, dart run build_runner build, dart format -l 120 (0 changed), dart analyze --fatal-infos (no issues), also after merging [586] Fix stale notes lists after renaming a label #587 and [566] Fix the backup location dialog interfering with shares #590 on top.