fix(superdoc): close public typedef gaps surfaced by SuperDoc.js probe (SD-2872) (#3046)

* fix(superdoc): close public typedef gaps surfaced by SuperDoc.js probe (SD-2872)

Probing `// @ts-check` against `packages/superdoc/src/core/SuperDoc.js`
(per the SD-2863 ratchet) surfaced 16 properties that the
implementation reads but the public JSDoc typedefs do not declare.
Each missing field is a customer-typeable property the runtime
supports today but TypeScript reports as unknown for consumers.

Adds:

  Config.useLayoutEngine
  Config.onFontsResolved
  Config.socket
  Modules.whiteboard
  SuperDocLayoutEngineOptions.virtualization (+ enabled, window, overscan)
  SuperDocLayoutEngineOptions.showBookmarks
  User.color
  Document.role

Verified locally: enabling `// @ts-check` on SuperDoc.js drops the
TS2339 errors against named typedefs from 17 to 1 (the remaining one
is a `Editor | PresentationEditor` narrowing issue, not a typedef
gap, and is in scope for SD-2867 phase 2).

This PR ships the typedef-side fix only. Enrolling SuperDoc.js under
the SD-2863 gate is tracked in SD-2867; ~137 unrelated errors
(implicit-any, loose `Object` typedefs, strict-null) need dedicated
cleanup before the gate enrollment.

* fix(superdoc): correct three typedef shapes from PR3046 review (SD-2872)

Codex review pass found three additions in the previous commit that
did not match runtime behavior:

- Document.role advertised a per-document override that does not
  exist. SuperDoc only writes `doc.role = config.role` internally;
  external collaboration overwrites it. Customers who set it on a
  per-document basis would see their value silently replaced. Removed
  the typedef.
- Modules.whiteboard rejected the `false` disable sentinel that
  use-whiteboard.js explicitly checks (`config === false`). Widened
  the type to `false | { enabled?: boolean }` so the runtime-supported
  shape compiles.
- Config.onFontsResolved typed the payload as `{ editor }`. The
  editor actually emits `{ documentFonts, unsupportedFonts }`
  (FontsResolvedPayload). Aligned with the public type already
  exported from `@superdoc/super-editor`.

Author: caio-pizzol

packages/superdoc/src/core/types/index.js

@@ -3,6 +3,7 @@
  * @property {string} name The user's name
  * @property {string} email The user's email
  * @property {string | null} [image] The user's photo
+ * @property {string} [color] Awareness color for collaborative cursors. Auto-assigned from the configured palette (or a default palette) when omitted, derived from a hash of the user's identity so the assignment is stable across reloads.
  */
 
 /**
@@ -536,6 +537,7 @@
  * @property {Object} [slashMenu] Deprecated. Use contextMenu instead.
  * @property {SurfacesModuleConfig} [surfaces] Surface system configuration
  * @property {TrackChangesModuleConfig} [trackChanges] Track changes module configuration
+ * @property {false | { enabled?: boolean }} [whiteboard] Whiteboard module configuration. Pass `false` to disable the module entirely; pass an object to opt in (with `enabled: true`) or to keep it registered but inert (`enabled: false`, the default when no field is set).
  */
 
 /**
@@ -628,6 +630,11 @@
  * @property {Object} [semanticOptions] Internal-only semantic mode tuning options.
  *   This shape is intentionally not a stable public API in v1.
  * @property {Object} [trackedChanges] Deprecated. Use `modules.trackChanges` instead. Optional override for paginated track-changes rendering (e.g., `{ mode: 'original' }` or `{ enabled: false }`).
+ * @property {Object} [virtualization] Page virtualization options for paginated layout. Defaults to `{ enabled: true, window: 5, overscan: 1 }` to render only the visible window of pages plus a small overscan buffer.
+ * @property {boolean} [virtualization.enabled] Whether virtualization is active (default: true)
+ * @property {number} [virtualization.window] Number of pages kept rendered around the active page (default: 5)
+ * @property {number} [virtualization.overscan] Extra pages rendered outside the active window for smoother scrolling (default: 1)
+ * @property {boolean} [showBookmarks] Whether bookmark indicators are shown in the rendered layout. Toggleable at runtime via `superdoc.setShowBookmarks()`.
  */
 
 /**
@@ -725,6 +732,9 @@
  * @property {string} [licenseKey] License key for organization identification
  * @property {SuperDocTelemetryConfig} [telemetry] Telemetry configuration
  * @property {ProofingConfig} [proofing] Proofing / spellcheck configuration
+ * @property {boolean} [useLayoutEngine] Opt-in toggle for the layout engine. Auto-disabled when web layout is requested without `layoutEngineOptions.flowMode === 'semantic'`; the loader logs a warning and falls back to the legacy ProseMirror render path in that case.
+ * @property {(payload: import('@superdoc/super-editor').FontsResolvedPayload) => void} [onFontsResolved] Callback fired after the editor reports `fonts-resolved`. The payload contains `documentFonts` and `unsupportedFonts` arrays so hosts can fall back, warn, or block printing on unsupported faces.
+ * @property {import('@hocuspocus/provider').HocuspocusProviderWebsocket} [socket] Internal: the shared websocket instance created by SuperDoc when `modules.collaboration.providerType === 'hocuspocus'`. Set automatically; do not pass from outside.
  */
 
 /**