booru/browser: Fix issue when clearing entry progress for the first time
booru/browser: Fix issue when clearing entry progress for the first time

When setting it to 0.0 for the first time, when not previously set, it
seems to be set to something like 0.1 for some reason.

ahodesuka/ahoviewer,ahodesuka/ahoviewer,ahodesuka/ahoviewer