demo(contract-templates): Locate button to scroll to a field or clause (SD-3314)

[caio-pizzol]

The contract-templates demo is our showcase for building custom UI on content controls, but nothing in it demonstrated jumping to a control from the side panel. This adds a Locate button on each field row and clause card that scrolls the document to that control - dogfooding the scroll-to API shipped in SD-3310 in a realistic sidebar.

It is scroll-only and named "Locate", not "Focus": it scrolls to the control but does not move the cursor into it. Building it surfaced the next two gaps in a real consumer - overlays drift while the document scrolls because there is no single geometry-change signal (SD-3311), and you cannot start editing right after locating because the cursor is not placed (SD-3312).

• Locate resolves the control by tag (selectByTag) and calls ui.contentControls.scrollIntoView({ id, block: 'center' })
• Field rows are restructured so the button is a sibling of the input (a <label> may not contain interactive content)
• Demo smoke test: clicking a lower clause's Locate scrolls its control into view

Verified: demo tsc --noEmit clean; demos/__tests__ contract-templates suite 2/2 (load + locate)

[linear-code]

SD-3314

[cubic-dev-ai]

cubic analysis

No issues found across 3 files

Linked issue analysis

Linked issue: SD-3314: contract-templates demo: Locate (scroll-to) for fields and clauses

Status	Acceptance criteria	Notes
✅	Add a "Locate" button on each field row that scrolls the document to that field's content control	Fields panel markup now includes a Locate button per field and an event listener that calls locateByTag for the field.
✅	Add a "Locate" button on each clause card that scrolls the document to that clause's content control	Clause card templates include a Locate button and the clause cards attach a click handler that calls locateByTag with the clause tag.
✅	Locate is scroll-only and uses the public scrollIntoView API (does not move the cursor into the control)	locateByTag resolves control by tag then calls ui.contentControls.scrollIntoView with block: 'center'; comments and code indicate it does not activate/focus the control.
✅	Field rows restructured so the Locate button is a sibling of the input (avoid interactive inside )	Fields row changed from a wrapper to a with an explicit and a sibling Locate .
✅	Include a demo smoke test that clicking a lower clause's Locate scrolls its control into view	A Playwright test was added which verifies the bottom clause starts off-screen, clicks its Locate button, and asserts the clause's painted element becomes visible.

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