- Remove backward compatibility for kebab-case SVG attribute keys
(fill-rule, stroke-linecap, stroke-linejoin) since svg-attrs are
already normalized to camelCase by the attrs->props migration.
- Remove unnecessary select-keys filtering and intermediate map
construction (dissoc :style + merge style).
- Directly extract values from style and attrs using or, avoiding
any intermediate map allocation.
Signed-off-by: Andrey Antukh <niwi@niwi.nz>