Restyle Inventory page as Pocket Ledger mobile concept

[Monster0506]

Summary

Restyles the Inventory page (/inventory) using the "Pocket Ledger" mobile design concept explored in design/mobile-mockups/c-pocket-ledger.html — a big total-value hero, floating item cards with category-inferred icon badges, and a pill "Add item" CTA — then reconciled it against the site's real design-system tokens so it matches the rest of the app's colorscheme (Pitt Royal blue / gold, glass surfaces) at every width, not a separate palette.

Changes

• Features/PhysicalAssets/Inventory.razor / Inventory.razor.css — page header restyled; no page-eyebrow (matches Physical Assets); desktop switches to the shared serif --font-display title and row layout.
• Features/PhysicalAssets/InventoryList.razor / InventoryList.razor.css — total-value hero card, item rows with category icon badges (electronics/housewares/pantry/furniture/apparel/generic), Edit/Delete moved into the expanded detail panel for a cleaner collapsed row (Revalue stayed in place). On desktop (min-width: 48rem) the item list becomes one glass pane with hairline-divided rows, matching NetWorthCalculator's .records-card pattern instead of floating cards.
• Components/App.razor — added Sora/Inter Google Fonts link (scoped .razor.css files can't use @import).
• Colors are token-driven end to end: the --pl-* custom properties resolve to the shared --brand/--glass-bg/--text/--accent-text tokens, so mobile and desktop render the identical palette — only the layout (floating cards vs. glass pane with hairlines, column vs. row header) differs by breakpoint.

Preserved

Every test-critical selector (.asset-row, .asset-row-summary, button.btn-primary, input[placeholder='Name'/'Category']) and all @code logic are untouched aside from two new pure helper methods (CategoryIconKey/CategoryIconMarkup).

Verification

• 240/240 tests pass (dotnet test)
• dotnet format / prettier --check clean
• Live-verified against the running container at 390px and 1440px viewports: empty state, populated list with real AI valuations, expand/collapse, Edit/Delete/Revalue all functional; desktop visually matches Physical Assets/Financial (same glass card, serif title, brand-blue buttons).