v0.1.1: value fixes from real-user validation

Fixes from the user-value audit (docs/USER_VALUE.md): spreadsheet never writes a partial file and adds group_by/aggregate queries (free cap 500 rows); time tracker carries currency and matches partial project names; price tracker refuses redirects off product pages, reports extraction confidence, and alerts are free; invoice prints currency on every amount and overdue report is free. Advisory file lock fixes cross-process lost writes. Built by theluckystrike. Pro keys at https://mcp.zovo.one