3be613c1

By: Michael Lynch <git@mtlynch.io>

Test caption updates through the media handler

Verify owner edits and clears persist, unauthorized updates leave captions
unchanged, and unknown media returns 404. Remove duplicate store-level tests
and inline the end-to-end caption edit steps.
configuredevShellx86_64-linuxbackendbackend-devcheck-bashcheck-frontendcheck-go-formattingcheck-go-test-packagescheck-trailing-newlinecheck-trailing-whitespacedeploy-to-flydiagramdocker-imagee2e-testsgo-testsimport-from-tinybeansjs-testslint-sqllittle-momentslittle-moments-devx86_64-linux