v1.0.1 — Fix Lunch Flow account linking

Fixes the 'currency' error when linking a Lunch Flow account whose account-list response has no currency.

The integration now reads the currency from the account balance when necessary, checks it against the local account, and displays a clear English/French message if Lunch Flow provides no currency in either response. The account picker no longer shows undefined.

Validated with 162 Python tests, including 11 regression cases for this fix, frontend syntax checks, real Home Assistant browser tests, hassfest and HACS checks. Lunch Flow responses are simulated; no live bank connection was used.

Update to 1.0.1 in HACS, restart Home Assistant, refresh the browser and retry linking the account. Existing accounts and transactions are preserved.