Fix false verification failures for browser ontology writes

[witbrock]

Merge decision: ready — authorised browser concept creation and description saves now verify the inputs actually persisted, while divergent effects remain indeterminate.

User outcome

Fix false verification failures reported after successful concept creation and description edits. Native Von task: #V#task_agent_e65d717fcdcec3fdf349b0cc5cc60280.

Material changes

• Respect a window's Personal selection and apply the governed actor-private creation default to persistence, including when SAIL is selected. Explicit organisation creation still requires the selected organisation and existing authority.
• Prepare description text, language, context and provenance once for both writing and verification. Preserve metadata and existing identical text values; use exact identity for case/spacing collisions. All three description HTTP endpoints share the governed operation.
• Use the window-aware browser API helper; retain drafts and explain indeterminate responses without fallback writes. Keep Save disabled while its request is pending.

Evidence

• 83 targeted backend tests pass, covering actual governed HTTP writes/read-back, Personal/SAIL, composite private restrictions, metadata preservation, text reuse, repeated edits, absent effects, wrong text/language/context/provenance, duplicate relations and creation scope mismatches.
• 7 frontend tests pass. Static lint: zero errors; 14 existing warnings.
• Authenticated Playwright replay using the real application and localhost browser-test login, with disposable in-memory MongoDB: creation and two description saves in each of Personal and SAIL; six successful canonical receipts; one exact description relation per concept. A separately identified simulated uncertain response retains the draft and makes one write.
• Browser evidence binds to product commit a02e9e4456fe343c49ca71183eda1ec0ac022686; the following commit only isolates an existing metadata unit test. Retained worker evidence: .run/ontology-verification/final/browser-evidence.json and screenshots. Repeatable fixture/scripts are included.

Ship boundary

Minimum evidence above is satisfied. Scope widening, false verification, duplicate effects or provenance loss remain stop-ship conditions. Existing private records are untouched. Local fixture acceptance does not establish public OAuth, MongoDB durability or broad system health. No deployment, DGX restart, schema migration, authority grant or unrelated ontology redesign is included.