Adding font and tagline as editable properties in Brand view

[pkras]

before:

after:

[bokelley]

A few things to look at:

Fonts can't be cleared once set. If a user previously saved fonts and later wants to remove them, clearing both font fields won't work — the save logic only writes fonts when at least one field is non-empty, so the existing values from currentEditStatus?.brand_manifest get spread in and persist. You'd need to either always write the fonts object (using undefined or null to clear) or add an explicit delete mechanism.

Tone data loss. When loading, manifest.tone is handled as either a string or an object (manifest.tone?.voice), but on save it's always written back as a plain string. If tone was previously stored as an object with additional fields beyond voice, those get dropped silently. Worth confirming that's intentional.

Nit: The changeset description says "slogan" but the form label is "tagline" — should be consistent.