feat(book): component gallery Vite app in apps/

[guanbinrui]

What

Adds apps/book — a plain Vite + React SPA that renders Maskbook's shared UI components. Not Storybook (removed in #10977); this is hand-rolled and deliberately small. Plan discussion in #12439.

Components are imported from source via the mask-src export condition, so the gallery tracks the packages with no build step of their own.

How it works

• Auto-discovery — drop a *.demo.tsx under src/demos/<section>/; import.meta.glob in src/registry.ts picks it up. First path segment = sidebar section.
• Resolve — vite.config.ts sets resolve.conditions: ['mask-src'], mirroring packages/mask/.webpack/config.ts. Without it @masknet/theme resolves to a .d.ts.
• Providers (src/providers.tsx) — MaskThemeProvider + light/dark toggle (localStorage), DialogStackingProvider, and DisableShadowRootContext so components render in the normal DOM instead of the extension's shadow roots.
• Router — ~20-line hash router; no rewrite config needed to deploy.
• wasm — vite-plugin-wasm is required because @masknet/shared-base re-exports @masknet/base, which loads tiny-secp256k1's wasm.

Sections

Section	Demos
Foundation	colors (live maskColor swatches), typography, shadows
Components	ActionButton, Alert, Indicators, LoadingBase, Tabs (base/round/flexible), TextField
Icons	full @masknet/icons gallery — 405 icons, filter + click-to-copy

Wiring

• pnpm-workspace.yaml: add apps/*
• root package.json: pnpm book (dev), pnpm book:build
• apps/book/vercel.json for deploy (Root Directory apps/book; build/install commands cd to repo root for the workspace)

Verification

• pnpm book:build passes (main chunk ~1.1 MB / 298 KB gzip, from the @masknet/base graph)
• Toured all 10 routes in headless Chromium: no console errors, light + dark both render
• Fixed one issue found in testing: this MUI fork's Stack takes alignItems only via sx, not as a prop — it was leaking to the DOM

Not in scope

Injection and Plugins sections need a mock layer (background Services.*, site-adaptor context, web3 providers) — tracked as P4/P5 in #12439.

🤖 Generated with Claude Code

https://claude.ai/code/session_013SLkuieqJXCMg1xoL98jij