feat(web): implement complete workspace with themes, tabs, sidebar, and mobile

Transform CalcText from a single-document calculator into a full workspace
application with multi-document support, theming, and responsive mobile experience.

- Theme system: 5 presets (Light, Dark, Matrix, Midnight, Warm) + accent colors
- Document model with localStorage persistence and auto-save
- Tab bar with keyboard shortcuts (Ctrl+N/W/Tab/1-9), rename, close
- Sidebar with search, recent, favorites, folders, templates, drag-and-drop
- 5 templates: Budget, Invoice, Unit Converter, Trip Planner, Loan Calculator
- Status bar with cursor position, engine status, dedication to Igor Cassel
- Results panel: type-specific colors, click-to-copy, error hints
- Format toolbar: H, B, I, //, color labels with live preview toggle
- Syntax highlighting using theme CSS variables
- Error hover tooltips
- Mobile: bottom results tray, sidebar drawer, touch targets, safe areas
- Docker multi-stage build (Rust WASM + Vite + Nginx)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

_bmad-output/C-UX-Scenarios/00-ux-scenarios.md

@@ -0,0 +1,42 @@
+# UX Scenarios: CalcText
+
+> Design experiences, not screens — every page serves a user with a goal and an emotion.
+
+**Created:** 2026-03-17
+**Phase:** 3 (Scenario Outline) + Phase 4 (UX Design)
+**Agents:** Freya (Page Specifications)
+
+---
+
+## Scenarios
+
+| # | Scenario | Pages | Description |
+|---|----------|-------|-------------|
+| 01 | Workspace Shell | App Shell, Status Bar | The overall 3-panel layout that contains everything |
+| 02 | Calculation Experience | Editor, Results Panel | The core — typing calculations, seeing results |
+| 03 | Document Management | Tab Bar, New Document, Rename/Delete | Multi-document workflow |
+| 04 | File Organization | Sidebar, Folder Tree, Templates, Recent/Favorites | Organizing calctext files |
+| 05 | Theming | Theme Picker, Preset Themes, Custom Theme, Accent Color | Personalizing the workspace |
+| 06 | Mobile Experience | Mobile Shell, Mobile Results, Mobile Sidebar | Responsive/touch adaptation |
+
+---
+
+## Page Index
+
+_Updated as page specifications are created during Phase 4._
+
+| Scenario | Page | Status | File |
+|----------|------|--------|------|
+| 01 | App Shell | Specified | 01-workspace-shell/1.1-app-shell/1.1-app-shell.md |
+| 01 | Status Bar | Specified | 01-workspace-shell/1.2-status-bar/1.2-status-bar.md |
+| 02 | Editor | Specified | 02-calculation-experience/2.1-editor/2.1-editor.md |
+| 02 | Results Panel | Specified | 02-calculation-experience/2.2-results-panel/2.2-results-panel.md |
+| 03 | Tab Bar & Document Lifecycle | Specified | 03-document-management/3.1-tab-bar/3.1-tab-bar.md |
+| 04 | Sidebar & File Organization | Specified | 04-file-organization/4.1-sidebar/4.1-sidebar.md |
+| 04 | Templates | Specified | 04-file-organization/4.2-templates/4.2-templates.md |
+| 05 | Theme System | Specified | 05-theming/5.1-theme-system/5.1-theme-system.md |
+| 06 | Mobile Experience | Specified | 06-mobile-experience/6.1-mobile-shell/6.1-mobile-shell.md |
+
+---
+
+_Created using Whiteport Design Studio (WDS) methodology_