Implement CE-WP-0001 Foundations: TS scaffold, lint boundaries, normalize v1, fixtures

T01 Toolchain — vite + pnpm 9.15 + React 18 + strict TS (ADR-0001).
T02 Folder layout — src/{shared,engine,anchor,source,binder,work,app}/
    mirroring the future subsystem split, with path aliases.
T03 Boundary lint — eslint-plugin-boundaries enforcing the dependency
    edges from wiki/DependencyMap.md §4; verified by a violating fixture.
T04 Canonical normalization v1 — src/shared/text/normalize.ts with
    NORMALIZE_VERSION=1; 10/10 vitest covering ligatures, CRLF, soft
    hyphens (including line-break reassembly), mixed whitespace.
T05 PDF fixture corpus — 7 user-supplied German PDFs in fixtures/pdfs/
    (gitignored binaries) plus a manifest with verbatim known-good
    quotes and page counts, ready for CE-WP-0002 selector tests.
T06 README upgrade — umbrella README points at wiki/docs/workplans
    and documents the dev workflow.
T07 ADR-0002..0006 stubs in docs/decisions/.

Toolchain end-to-end: pnpm install + lint + typecheck + test all green.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docs/decisions/ADR-0001-toolchain.md

@@ -0,0 +1,68 @@
+# ADR-0001 — Toolchain (Vite + pnpm + React 18 + strict TypeScript)
+
+- Status: accepted
+- Date: 2026-05-24
+- Workplan: CE-WP-0001-T01
+
+## Context
+
+`citation-evidence` is the umbrella repo for an MVP that will eventually be
+segmented into six packages (`shared/engine`, `anchor`, `source`, `binder`,
+`work`, `app` per `wiki/DependencyMap.md`). We need a single toolchain that:
+
+1. Gives a fast inner dev loop for a React-based reference workspace.
+2. Plays well with a future pnpm workspace split (so each `src/<name>/` folder
+   can become a workspace package with a `git mv` and a `package.json` cut).
+3. Provides first-class TypeScript with the strictest practical settings — the
+   shared contracts in `wiki/SharedContracts.md` only pay off if the type
+   system actually enforces them.
+4. Has a credible unit-test story for the engine/anchor/source pure-logic code
+   and an integration path for the UI later.
+
+## Options considered
+
+- **Vite + pnpm + React + Vitest** *(chosen)*
+  - Fast HMR; well-supported React plugin; Vitest shares the Vite pipeline so
+    tests use the same module resolution as the app.
+  - pnpm workspaces are the most ergonomic path to the eventual multi-package
+    split.
+  - React 18 because the PRD's reference workspace is a desktop-class web app
+    and the ecosystem (PDF viewer libraries, drag-and-drop, etc.) targets it.
+
+- **Next.js (App Router)**
+  - Heavier than needed for a local-first reference workspace; SSR/route
+    handlers add complexity the MVP doesn't use.
+  - Harder to split into independent packages later.
+
+- **tsc-only + custom runner**
+  - Simplest, but no HMR and we'd hand-roll the React + bundler integration.
+    Pointless overhead for a UI-centric project.
+
+- **Bun / Deno**
+  - Toolchain bets that would add risk to the PDF/viewer integration spike,
+    which is already the highest-risk part of the project (see
+    `CE-WP-0002-T02`).
+
+## Decision
+
+Use **Vite 5** + **pnpm 9** + **React 18** + **TypeScript 5 with `strict`,
+`noUncheckedIndexedAccess`, `exactOptionalPropertyTypes`, `noImplicitOverride`,
+`noFallthroughCasesInSwitch`, `verbatimModuleSyntax`** turned on. Use
+**Vitest 2** as the test runner. Node version pinned to **20.10.0 LTS** via
+`.nvmrc`. Path aliases (`@shared/*`, `@engine/*`, etc.) map to `src/<name>/*`
+so import sites read the same whether or not the folder is later extracted.
+
+## Consequences
+
+- Bumping React or Node is a deliberate, ADR-worthy change.
+- The eventual pnpm workspace split keeps the same import names — each
+  package's `name` becomes `@citation-evidence/<folder>` and the path aliases
+  are replaced by package resolution. No source-code churn required.
+- Vitest's Vite-aware resolution means a contract test that imports across
+  partitions will fail at the same boundary that production code would —
+  there is no test-only loophole.
+- ESLint rules enforcing the dependency map (CE-WP-0001-T03) layer on top
+  cleanly: `eslint-plugin-boundaries` reads the same `tsconfig` paths.
+- No application dependencies are installed in this task — only the toolchain.
+  Subsequent workplans install PDF, drag-and-drop, etc. on demand and record
+  them in their own ADRs where the choice is non-obvious.