Improve behavior authoring and typed trace history (untested checkpoint)

harness/DECISIONS.md

@@ -211,6 +211,57 @@ Decision: retain same-layer admission for ordinary diagrams, but allow both-laye
 
 Alternatives rejected: filtering every view by its labelled layer loses existing Traceability content; ignoring layer validation everywhere hides mistaken references; serializing temporary GUI filters breaks source/API parity. Revisit if native workflows or cross-layer regression evidence exposes ambiguity. Current implementation is pending integrated tests and native acceptance, not an established release result.
 
+## Continuous behavior authoring — 2026-09-10
+
+Problem: adding the first Exchange to an empty process changed its interactive
+Graph into an ordered sequence Scene without gesture tools. Scenario non-message
+creation discarded the visible operand and insertion point, defaulting to root
+append. These are verified source paths; new-binary native acceptance is pending.
+
+Select one interactive process renderer. Project legacy ordered adjacency as
+endpoint pairs without fabricated semantic relation IDs. Loading and selecting
+remain read-only. The first topology mutation uses the existing validated batch
+to materialize unaffected adjacency and splice the chosen insertion atomically.
+Reject the alternative of a special 0/1-element renderer exception, which would
+reintroduce the discontinuity at a later element count; also reject automatic
+load-time migration and artificial self-links. Core legacy/explicit semantics
+and the source version are unchanged. Revisit if actual imported-path editing
+cannot preserve ordering, rejection and exact source/Undo behavior.
+
+Scenario Action, State, Reuse and empty Fragment creation capture the clicked
+owner, operand, before-occurrence and optional lifeline before starting the
+existing typed draft. Keep current validation, recovery and atomic history.
+Fragment range wrapping and cross-operand movement require separate explicit
+transactions. Do not infer persisted lifeline geometry from a click: the current
+model does not store horizontal lifeline order. Reused-scenario navigation uses
+bounded transient caller/use context, never an extra model history entry.
+
+Evidence and acceptance: `release-behavior-audit-20260910.md`, Gitea #1, new
+production-pointer regression paths and independent source reviews. Compilation,
+automated execution and native validation are still pending at this decision.
+
+## Typed stored observations — 2026-09-10
+
+Problem: generic trace-baseline Add inserted a UUID string into the closed
+FacetReview list, producing an invalid draft. Hiding Add and routing only to
+current review/reset cannot fulfill the normative contract: historical values
+and references may be valid even when their live definitions no longer exist.
+
+Select an explicit advanced typed history editor over the existing OpenAPI
+TraceBaseline/FacetReview descriptors. They provide the finite shape catalog
+already required for REST parity; final authority remains core typed decoding,
+historical admission and one EditTrace through Document. Preserve invalid raw
+drafts, exact historical UUID text, optional/Observed alternatives and explicit
+constructor selection. Current observations may be copied only by a deliberate
+action. Cache the descriptor and bound recursive rendering; unsupported shapes
+must fail visibly instead of generating an invalid default.
+
+Reject a separate handwritten GUI metamodel or a new duplicate core type-shape
+catalog, and reject raw JSON as the sole graphical editing surface. Revisit if
+descriptor/core consistency or native usability cannot be verified. This choice
+is under implementation; it does not yet close the parity finding in
+`release-end-state-audit-20260910.md`.
+
 ## Basic canvas authoring — 2026-09-07
 
 The user rejected the large horizontal creation row. Actual installed Capella 7.1