Consistent language handling, due dates on widgets, and documentation accuracy

This pass makes your language choice stick everywhere, and brings our documentation in line with how things actually work.

• When you pick a language yourself, that choice now always wins — including speech recognition and emails, where some paths still followed the browser language
• Fixed password-reset and other emails arriving in Korean for people using unsupported languages — they now arrive in English
• On narrow screens, opening a note from the AI panel now closes the panel instead of leaving it stacked behind
• (Android) Day, 3-day, and week widgets now show due dates — items with only a deadline used to be invisible there (ships with the next app update)
• (Android) Widget colors now match your category colors in the app
• Corrected the privacy policy, terms, and pricing FAQ to match actual behavior — the scope of the access-request window, our AI processing vendors, and how automatic data cleanup works
• Plus general stability improvements