Bump Metroflip to v2.0

[luu176]

Application Submission

This is the v2.0 update (from v1.0). What changed since the last version:

New UI:

• Redesigned "card view": a paged, scrollable interface with an animated header
  icon, replacing the old flat text output. Used consistently across every card
  type and the About page.

Card support / reading:

• Every parser now displays through the card view, including Calypso
  (Navigo / Opus / Rav-Kav) and T-money, which were converted from the old UI
• Calypso: added support for Navigo paper / anonymous tickets and hardened the
  decoder against short/malformed responses
• Suica: fixed several reading crashes and corrected the Octopus balance display

Stability & memory:

• Card view is now built on the main thread to avoid NFC-worker-thread UI races
• Fixed protocol-detection, saved-file loading, and poller-lifecycle bugs
• Plugged memory / handle leaks across parsers and raised the app stack so
  saved-file parsing no longer overflows it
• Fixed the scan LED staying lit after backing out of a read without tapping

Also added the GNU GPLv3 license.

Author Checklist (Fill this out)

• I've read the contribution guidelines and my PR follows them
• I own the code I'm submitting or have code owner's permission to submit it
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have validated the manifest file(s) with python3 tools/bundle.py --nolint applications/CATEGORY/APPID/manifest.yml bundle.zip

Reviewer Checklist (Don't fill this out!)

• Bundle is valid
• There are no obvious issues with the source code
• I've ran this application and verified its functionality