[masarray]

Documentation-only design proposal.

Defines a two-panel Browser workspace with virtualized TreeGrid + DetailGrid, canonical model and read-only inspection integration, source-aware values, Setting Group requirements, performance budgets, and deterministic acceptance criteria.

No GUI, protocol, reporting, or engine code changes.

Before implementation, identify and preserve the exact verified Browser build matching the operator screenshot.

[masarray]

D16 historical reconciliation — CLOSE AS SUPERSEDED DESIGN PROPOSAL, NOT MERGED.

Evidence checked against protected integrated RC 817c3910e8223fa2ac531a4426ada5d2d4bbbe50 (ARSAS v1.6.42 stable unchanged):

• The entire PR changes exactly one path, docs/architecture/ARD_IED_BROWSER_ENGINEERING_WORKSPACE.md; it contains no application, engine, test or workflow changes.
• The document itself labels its status PROPOSED / DESIGN ONLY, audits an Oct 13 pre-Browser main, and explicitly says it is not authorization to modify IEC 61850 protocol/control behavior.
• The historical document file is absent from the modern integrated RC architecture directory. This is not a byte-identical merge and must never be reported as such.
• The Browser has since been developed through the M1/M2 engineering PR lineage (Browser M1: virtualized two-panel engineering tree and detail presentation #547 onward); current RC is an evolved implementation. Reintroducing the original planning document as a pending standalone PR would misleadingly present an obsolete pre-implementation architecture as the current specification. Important still-open semantics/physical acceptance remain tracked independently (e.g. M2.14 Browser: surface RCB discovery-state fields with exact provenance #594, M2.14 Browser Files: one verified COMTRADE record per row, compact native grid #595, M2.14 IED Browser: collapsible RCB control and last-report sections #599, M2.17-D Field convergence: GoCB passive evidence, SGCB initial status, RCB/Read correctness #606, P0 follow-up: retire unresolved MMS control sessions without blocking reconnect #615).

Decision: retire this documentation-only proposal as superseded / not planned. GitHub retains its full original design and discussion for reference. This closure neither asserts every aspirational ARD requirement was implemented nor authorizes merging RC, engine repin, release promotion or physical IED FAT. No source changes made.