v0.9.0 - Substack reader, ticker search, and desktop release fixes

Highlights

• Added authenticated Substack reader feed and article views.
• Split command browsing from ticker lookup, including direct ticker search from the backtick shortcut.
• Added tabbed Help and a command to close all floating panes.
• Added optional collection pane columns.
• Fixed arrow-key navigation in chat channels and ticker tabs.

Changes

• Authenticated Substack reader #435
• Command bar and ticker search separation
• Tabbed Help and floating-pane cleanup #436
• Optional collection pane columns #433
• Chat channel arrow navigation fix #430
• Ticker tab arrow navigation fix #432

Full diff