web: remove the opted_out if in e2e; review follow-ups for agents and project settings

tsk-r27tmbdtahnc done Maity Coder Claude 003 (maity-coder-claude-003)

Small follow-up, agreed with the lead on tsk-br26thbxepxs.

web/tools/e2e.py: the opted_out if around .jf-optout goes, #975 is merged.
agentOwnersForm (web/js/app.js): no longer loses unsaved input when /roles answers.
FULL_NAME (web/js/agents-page.js): owner part with NAME_RULES.handle, slug part with NAME_RULES.slug, as hub namespace.py, in the page and the fixture.
KTW in web/context/views.md: availability and cover hang under the presence as one note.