EANCH-WP-0001 T05 (prep): make root a full barrel for umbrella cutover

The umbrella's DOM tests vi.mock the single @anchor/index barrel (spreading
the original and overriding PdfSpikeViewer). To keep the cutover a mechanical
specifier swap and preserve those mocks, the evidence-anchor root re-exports
the full surface (pure core + PDF adapter), matching the prior @anchor/index.
evidence-anchor/pdf remains a focused viewer entry. Viewer code still lives
only under src/pdf/ (eslint-enforced). Repo stays green: 30 tests, tc, lint.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -62,13 +62,14 @@ Boundary rules for the layout (enforced by `eslint.config.js`):
   are confined to `src/pdf/` — the pure zone (`src/selectors/**`, `src/types.ts`)
   may not import them;
 - `src/selectors/` is pure and depends only on `citation-engine` shared types;
-- the **root** entrypoint (`evidence-anchor`) exposes only the pure surface —
-  `createSelectors`, `resolveSelectors`, the selector/resolution types, and the
-  `DocumentViewerAdapter` contract;
-- the concrete PDF adapter is reached through the **`evidence-anchor/pdf`**
-  subpath, so pure consumers never pull PDF.js or React into their bundle. That
-  adapter is still the explicitly-named `PdfSpikeViewer` spike; promoting it to
-  a production `PDFViewerAdapter` is registered follow-on work (T06).
+- the **root** entrypoint (`evidence-anchor`) is the full barrel — selector
+  creation/resolution, the adapter types/contract, and the PDF adapter — so
+  consumers resolve every anchor symbol (and their test `vi.mock(...)` calls)
+  from a single specifier, matching the umbrella's prior `@anchor/index`;
+- a focused, viewer-free entry is also published at **`evidence-anchor/pdf`**
+  for consumers that want the PDF surface explicitly. The concrete adapter is
+  still the explicitly-named `PdfSpikeViewer` spike; promoting it to a
+  production `PDFViewerAdapter` is registered follow-on work (T06).
 
 ## Public API (target surface)