issue 1690 slice 3: system-def field control properties #4440

Parent

Parent: #1690

Workbench inventory P1 (system definition). Field property save / add / delete already ships. Remaining: operators can set control properties on a system-def field. REST currently documents control/stylesheet/flow as unsupported (SystemDefResource addField description).

Slice goal

One user-visible increment: An Admin can view and save control properties for a system-definition field from Developer → System definition, via a new or extended REST contract (IPSContentDesignWs system def — no new SOAP), with Playwright + product-docs.

HARD BAN: do not split REST vs SPA vs Playwright. Do not take stylesheet editor or application-flow editor in this PR (file a residual if needed). Do not stack with slice 1 or 2.

In scope

1. REST: Admin GET/PUT (or field-scoped path) for system-def field control properties; path-safe field names; 400/403/404/409; wrap root matching peers.
2. sitemanage IXxxAdaptor impl; Mockito resource test; Spring test stub adaptor on rest test classpath; sitemanage adaptor tests.
3. SPA on SystemDefPanel (or field detail): edit control properties; Save uses request lock released on save (same as existing system-def writes).
4. Surface-filtered Playwright on QA H2.
5. Update product-docs/8.2/admin/developer-system-def.md and system-def section of product-docs/8.2/developer/rest.md.

Out of scope

• Stylesheet source editor and application-flow editor (later residual)
• Item-filter rules (slice 1)
• Shared-field nested editor (slice 2)
• Shim / template-assembler Phase 5 docs (issue 2632 slice 5: product-docs XSL support statement and migration cookbook #4434/issue 2632 slice 6: product-docs definition-XML dual-run upgrade path #4435)

Acceptance

• Admin can persist at least one control property on a system field; GET round-trips; non-Admin 403
• rest + sitemanage standalone mvnw clean install green; WebUI Vitest for the panel
• Playwright surface spec green on QA H2
• Product-docs match shipped behavior; [8.2] Developer module — post-P0 follow-ons #1690 Agent progress updated

Modules

rest, projects/sitemanage, WebUI, modules/perc-qa-automation, product-docs/8.2/

Leave unassigned. Do not add In Progress.

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