v1.9.1 - SQLite and In-Deck indicator

[DredBaron]

What changed and why

Adds feature to show if a card is used in a deck when selecting for trading, and on the main Collection page.

Also adds new database type SQLite to pick from on instance creation via new docker-compose.yml templates.

• Bug fix
• New feature
• Refactor / chore
• Documentation

Testing

Added test coverage for SQLite migrations, and CI checks a from-scratch migration for both databases on every push.

• pytest passes with no warnings
• npm run lint passes (frontend changes)

None

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Note: Purely AI-generated code is not accepted. By submitting this PR you confirm the code is human-written or human-reviewed.