feat(SurveyFormBuilder): redesign the blocked section

[warcos-fact]

Description

Redesigns the blocked (locked) section in the SurveyFormBuilder. Extracted from #4307 (co-creation patterns) so the SurveyFormBuilder/F0TagRaw changes can be reviewed and merged on their own; #4307 is stacked on top of this branch.

A locked section now reads as a single muted grey rounded panel with a white "Locked" tag in its title, replacing the previous explanatory alert.

Screenshots (if applicable)

Light	Dark
Grey rounded-2xl panel wrapping the section header + its question cards, white "Locked" tag at the right of the title, white default cards inside.	Same treatment using semantic tokens.

(Storybook: Surveys → SurveyFormBuilder → Default.)

Implementation details

• Whole-section panel: a locked section's header + its questions are grouped into one rounded-2xl bg-f1-background-secondary wrapper (Form/index.tsx). Verified safe inside Reorder.Group (framer-motion orders by measured position + context, not DOM nesting; locked items aren't draggable).
• Alert → "Locked" tag: the section notice/alert is removed; a white F0TagRaw (lock icon + "Locked") sits at the right of the title. The section description is no longer shown inline — it's surfaced as an instant tooltip on the tag.
• Cards: locked question cards roll back to the default white card styling, drop the hover-border effect, and force the not-allowed cursor on every descendant ([&_*]:!cursor-not-allowed). Right padding mirrors the drag-and-drop gutter so all cards share the same width.
• F0TagRaw: adds an optional className passthrough (backward compatible) so the tag can render white.

Builder-only: the answering/preview renderer (SurveyAnsweringForm) is untouched and shows locked sections as regular questions.

[github-actions]

✅ No New Circular Dependencies

No new circular dependencies detected. Current count: 0

[github-actions]

🔍 Visual review for your branch is published 🔍

Here are the links to:

• the Visual Review Page

• the latest build on chromatic

• the full storybook

[github-actions]

✅ No breaking public API changes

No public exports were removed, renamed, or had existing props/types changed in a breaking way compared to main.

Comparing f0, experimental and ai against main. Adding components, types, or optional props is safe. This check is non-blocking.

⚠️ Could not analyze f0 (no-head), experimental (no-head), ai (no-head) — a build may have failed; results may be incomplete.

[warcos-fact]

Closing: the blocked-section redesign can't be cleanly extracted onto main — it depends on cocreation-branch additions (the question-level notice prop and the surveyFormBuilder.labels.locked i18n key) that aren't on main, and pulling those in cascades into broader cocreation work. Keeping this work in #4307 instead.