1.8.4 - user management & bugfixes

• Bugfix: 52-week high and low values were swapped when computing portfolio summary volatility
• Feature: Admins can change any user's password via the Users screen (new per-user actions menu: edit profile, change password, delete)
• Bugfix: Yahoo chart parsing more tolerant (empty quote arrays and missing ticker names no longer break chart loading)
• Minor UI polish: dropdown menu headers, clearer user delete confirmation
• Tests: Added extensive test coverage for auth, cache, CSV import, enrichment, validation, and date/range parsing

What's Changed

• bugfix for #38 by @venil7 in #39
• version bump 1.8.4 by @venil7 in #40

Full Changelog: 1.8.3...1.8.4