* feat(share): export the share-view codec for host servers
Add `@gods-eye-view/core/share/view-codec` (src/share/viewCodec.js) as a
package export with its own boundary group. The codec is pure (no DOM, no
Cesium, no external dependencies), so a host's server can decode a
/share/<code> link, for example to describe the view in link previews.
* feat(share): export the share-link address helpers
Add `@gods-eye-view/core/share/link-path` (src/share/shareLinkPath.js), so a
host's server reads /share/<code> addresses the way the app does.
