feat(sdk): export internal types from public index for bundler resolution [SPA-4097] (#1596)

* feat(sdk): export internal types from public index for bundler resolution

These types were previously only reachable via internal dist/ paths
(e.g. @contentful/live-preview/dist/types), which worked under
moduleResolution:node but fails under moduleResolution:bundler (Angular
v21 default) because unlisted exports map entries are rejected.

Exports added: Argument, SubscribeCallback, InspectorModeDataAttributes,
InspectorModeEntryTags, InspectorModeTags.

Adding them to the public index entry is additive and non-breaking.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

* chore(sdk): revert test additions for type-only exports

Co-Authored-By: Claude Opus 4.7 <[email protected]>

---------

Co-authored-by: Claude Opus 4.7 <[email protected]>

Author: Chaoste

packages/live-preview-sdk/src/index.ts

@@ -409,3 +409,10 @@ export { LIVE_PREVIEW_EDITOR_SOURCE, LIVE_PREVIEW_SDK_SOURCE } from './constants
 
 export * from './messages.js';
 export { encodeGraphQLResponse, encodeCPAResponse, splitEncoding, parseAttributesFromHref };
+
+export type { Argument, SubscribeCallback } from './types.js';
+export {
+  InspectorModeDataAttributes,
+  type InspectorModeEntryTags,
+  type InspectorModeTags,
+} from './inspectorMode/types.js';