Forms: surface common fields first in the block inserter

[dhasilva]

Fixes DSGCOM-690

Proposed changes

When adding a field inside a Form block, the inline "quick inserter" (the + between fields) shows only 6 blocks. That set is driven by the Form block's prioritizedInserterBlocks setting, which overrides Gutenberg's usage-based ("most used"/frecency) ordering for those slots — so the visible fields are fully deterministic, not per-user.

Until now that list was derived from the raw array order in child-blocks.js, which happened to surface incidental fields (Checkbox, Consent, Date, Dropdown, Hidden, Email) and pushed the most commonly used fields — Name (~8th), Text (~11th) — past the 6-item cutoff. They never appeared by default no matter how often a user inserted them.

• Add an explicit FEATURED_INSERTER_FIELDS order — Name, Email, Text, Textarea, Select (Dropdown), Checkbox — used to build PRIORITIZED_INSERTER_BLOCKS.
• Remaining valid fields follow after the featured ones in their existing child-blocks.js order, so nothing is removed — only the top 6 change.
• No behavior change to allowedBlocks or anything else; the constant is only consumed by useInnerBlocksProps for inserter ordering.

Related product discussion/links

• Linear: DSGCOM-690

Does this pull request change what data or activity we track or use?

No.

Testing instructions

• Create or edit a post/page and add a Form block.
• Click the inline + appender inside the form (the quick inserter) — do not type in the search box.
• Before: the 6 default blocks include Hidden field and omit Name/Text.
• After: the first 6 are Name, Email, Text, Textarea, Dropdown (Select), Checkbox, in that order.
• Confirm the order is identical on a brand-new site and on a heavily-used one (it is deterministic and not affected by usage history).
• Typing in the search box still surfaces every field (e.g. search "hidden" → Hidden field) — only the default ordering changed.

[github-actions]

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[github-actions]

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Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/packages/forms/src/blocks/contact-form/edit.tsx	0/344 (0.00%)	0.00%	5 💔

Full summary · PHP report · JS report

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