The plugin parser's parse-point returned a plain `{:x … :y …}` map,
but shape interaction schemas (for example schema:open-overlay-interaction)
require the attribute to be a `::gpt/point` record. `(instance? Point {:x 0 :y 0})`
is false, so validation silently rejected plugin `addInteraction` calls
that passed `manualPositionLocation`; only a console warning was produced.
Change parse-point to return a `gpt/point` record via `gpt/point`.
All three call sites (parser.cljs:open-overlay, plugins/page.cljs,
plugins/comments.cljs) continue to work because Point records support
the same `:x`/`:y` access plain maps do.
Add a unit test that covers nil input and verifies the returned value
satisfies `gpt/point?`.
Github #8409
Signed-off-by: FairyPigDev <luislee3108@gmail.com>
Signed-off-by: Andrey Antukh <niwi@niwi.nz>
Co-authored-by: Andrey Antukh <niwi@niwi.nz>
