NFC tag support for one-tap chore completion

[Wikid82]

Why

Writing an NFC tag and sticking it to a physical object (e.g. the washing machine) lets a phone tap complete the associated chore instantly — a nice physical-world shortcut for recurring chores.

Proposed approach

• Use the Web NFC API (NDEFReader) to read/write tags associating a tag with a chore ID
• Platform limitation: Web NFC is currently Android Chrome only — no iOS Safari support. Note this clearly in the UI when the API is unavailable rather than failing silently
• Tapping a written tag while the PWA is open/foregrounded marks the chore complete

Depends on

#32 (PWA foundation).

Acceptance criteria

• An NFC tag can be written from the app and associated with a chore
• Tapping the tag on a supported Android device marks the chore complete
• Unsupported browsers (iOS) get a clear message instead of a broken feature