fix(desktop): simplify duplicate agent provenance

[wesbillman]

Summary

• leave the local same-name agent row unlabelled because locality is implied
• mark only the remote identity with a compact monitor badge reading Other setup
• suppress the redundant managed by you text for duplicate owned agents while retaining distinct short npubs and exact-pubkey routing

Testing

• node --import ./test-loader.mjs --experimental-strip-types --test "src/**/*.test.mjs" (5,129 passed)
• node_modules/.bin/tsc --noEmit
• focused Biome check on the three changed files
• focused Playwright smoke test: duplicate owned agents preserve provenance and exact pubkey selection
• visual inspection at 1280×720

[wesbillman]

Add small cloud icon for now to indicate if agent is running on a difference instance of Buzz.

[jedwards27]

:bot: Jude’s code review agent

Verdict: REQUEST CHANGES
Reviewed: 2e7583bf5ad5926ca32367af9954bc79d108e42d..aadfe147640e624d4be1528423b436b75e584bda (exact live head aadfe147640e624d4be1528423b436b75e584bda)
Risk: medium — user-visible identity provenance at an ambiguous same-name selection boundary.

Blocking finding

The promised visible Other setup badge is absent, and its replacement disclosure is unreachable in Channel members.

desktop/src/features/agents/ui/OtherSetupAgentMarker.tsx:18-27 renders only a 12px cloud glyph. “From another Buzz setup” exists only as its accessible name and delayed tooltip; no visible Other setup text is rendered. In Channel members, that trigger is nested under the pointer-events-none identity subtree at desktop/src/features/channels/ui/MembersSidebarMemberCard.tsx:163-195, so a sighted pointer user cannot open the tooltip to learn what the unfamiliar glyph means. Mention suggestions likewise expose an unfocusable marker inside rows with tabIndex={-1} (desktop/src/features/messages/ui/MentionAutocomplete.tsx:127-142), leaving no keyboard disclosure.

The new E2E explicitly asserts that the remote row does not contain Other setup (desktop/tests/e2e/mentions.spec.ts:381-387), locking in the opposite of the PR’s visible-badge contract without checking tooltip reachability.

Please render a compact persistent Other setup text badge/chip on only the remote identity in both surfaces, keep the local row unlabelled and retain the short npubs, then cover visible text, keyboard selection, and a narrow viewport. A tooltip can remain supplementary, but provenance should not depend on it.

Contracts traced

Exact-pubkey routing remains intact: candidate coalescing is pubkey-keyed, selection records the chosen pubkey, and send-time revalidation refreshes managed/relay ownership before admitting tags (desktop/src/features/messages/lib/useMentions.ts:249-303,721-815; desktop/src/features/messages/lib/agentMentionRevalidation.ts:47-101). isOtherSetupAgent correctly excludes exact local managed-agent matches and requires viewer ownership (desktop/src/features/agents/lib/otherSetupAgent.ts:4-36). No relay protocol, IPC, persistence, or tenancy contract changed.

Validation at matching clean head

• Full Desktop JS suite: 5,129/5,129 passed.
• TypeScript typecheck: passed.
• pnpm build:e2e plus focused duplicate-owned-agent Playwright journey: 1/1 passed; exact pubkey tags remained distinct.
• Exploratory built-UI hit test reproduced that the Channel-members marker receives no pointer target.
• Focused provenance/mapping rows: 7/7 passed; just file-size-check and git diff --check passed.
• CI at final sample: macOS build and both Desktop integration shards passed; Desktop Core and four smoke shards were still in progress.

Residual risk: focused UI evidence used the renderer/mock bridge, not native WKWebView or a live relay. Native harness was absent from this checkout. Those gaps do not weaken the reproduced blocking UI failure.