Release notes.

Added

• Automatic updates: the app checks for a newer installer on launch, downloads it in the background, and installs it the next time you restart. A banner tracks the download and offers "Restart now".
• "What's new" panel on the first launch after an update, and a Releases page on the download site — both generated from this changelog.

Added

• Fleet tab for managing trains separately from line planning.
• Real signal holding — trains wait at held signals instead of passing through.

Changed

• Reworked track connections and the curve engine for smoother alignments.
• Density overlay and UI consistency pass across panels.
• Saves now live in a visible `Documents/Transit Architect` folder instead of the hidden per-OS application-data directory.
• Clearer tutorial and onboarding copy.

Fixed

• Track curve geometry near stations no longer kinks or overshoots.

Added

• Full simulation engine — commuters with real origins and destinations choosing between transit, walking, and driving based on time, transfers, waiting, crowding, and fare.
• Worldwide population and activity data; start in thousands of real cities.
• Track and station editing, service planning (stopping patterns, headways, operating windows, fares, fleets), finances, and IPO/loans.
• Save system with automatic rotating backups.
• In-game tutorial/onboarding and a tester feedback panel.