[ra-co88]

Closes the A11Y-6b finding and the A11Y-13/14/15/16 re-do. Branch cut fresh from develop (per the lesson from #15's mid-flight squash merge), three commits, each verified to contain the files it describes.

A11Y-6b — state carried by shape, not colour

The indicator was a bare coloured span using saturated red/green/amber. Measured before fixing, under a deuteranopia simulation (Brettel/Viénot):

pair	normal vision	deuteranopia
running–failed	1.65:1	1.10:1
running–stopped	1.19:1	1.31:1
stopped–failed	1.96:1	1.44:1

At 1.10:1 running and failed are visually identical. The obvious fix — a better palette — is falsified by measurement: brute-forcing hue/luminance combinations across the three groups topped out at 1.57:1, still far below the 3:1 WCAG asks for non-text UI. Colour cannot carry this signal, so shape now does:

• running — solid disc
• created / stopped — hollow ring (present but inert)
• starting / stopping — half-filled ring (in transition)
• failed / error — square (the only non-round shape, legible in greyscale)

Colour is retained as reinforcement, with darker values that all clear 3:1 against white (3.36–6.47:1). The old #22c55e was 2.28:1 and genuinely failed 1.4.11 — the test reports that exact figure when reverted.

A defect the shape change exposed: AgentCard mapped starting/stopping to the same amber as stopped/created, so "starting up" and "shut down" were indistinguishable there. Its palette is now aligned with the dots so one agent state reads the same everywhere.

Accessible names: all three dot sites are now aria-hidden. The second (dropdown item) and third (Select option) had neither aria-hidden nor a text alternative, so colour was their only carrier. selectOption now threads a state label into the Select option's accessible name, which previously carried only the disconnected case. AgentCard was already accessible — it renders formatAgentState() as text — so only its palette changed.

A11Y-13 — decorative icons

Three Lucide SVGs in ServiceRestartOverlay (Power, CheckCircle, AlertTriangle) were unlabelled. They are decorative — the adjacent text already states the phase — so each is aria-hidden rather than given a redundant label.

A11Y-15 — the drop zone was unreachable by keyboard

It was a <div> with onClick and nothing else: no role, no tabIndex, no key handler. A keyboard user could not reach it at all, and Enter or Space did nothing. Now role="button" + tabIndex + explicit Enter/Space handling, with preventDefault on Space so it does not also scroll the page.

While busy it takes tabIndex={-1} and aria-disabled, and the click handler is guarded. That branch is tested, not assumed — parsing runs inside handleConfirm, so a hung parser promise holds busy=true with the zone mounted.

A11Y-14 — truncated id with no way to read it

CopyableResourceId's inline variant renders label: value into a span that truncates with an ellipsis, and there was no title anywhere. A long id was unrecoverable by sight while the button's accessible name still carried the full string — which is exactly why a screen-reader-only check would have missed it. Title added on the button (not the inner span) so it applies whichever text node is clipped, and it is additive: real text content untouched, accessible name unchanged.

A11Y-16 — no fix needed, it was already done

The inventory row read "tabIndex = 0" as evidence of a live defect, but ExpertColorPicker already renders real <button>s with aria-label/aria-pressed, aria-hidden swatches and role="group". Native buttons need no tabIndex. A grep count is not a finding — "0 tabIndex" can mean "already accessible". Recording this so the row stops being re-queued.

Test plan

• npx tsc -b → clean
• npx eslint on changed files → 0 errors
• New: AgentSelector.stateIndicator.test.ts (6), 1 added to AgentSelector.a11y.test.tsx, 3 added to SkillImportModal.test.tsx, CopyableResourceId.a11y.test.tsx (3)
• Mutation-verified: reverting failed to round fails the shape case; restoring #22c55e fails the contrast case with the 2.28 figure; removing onKeyDown fails only the Enter/Space case; removing role/tabIndex/aria fails all three; removing the title fails the two title cases while the accessible-name case keeps passing (which is the point — the title is additive).

Notes

• Pre-existing, load-order-dependent vitest failures unrelated to this branch (AuthGuard, AvatarDropdown.displayName, EmojiPicker, PdfDocumentPreview.windowed, DocumentPreviewCore.docxSanitize, RootDirSelect.expand, TeamMemberPicker). Baseline-verified by stashing this branch and re-running: they fail identically. src/pages/Experts alone is 83/83.
• Neither CI nor make all runs vitest, so these are outside the ship bar — but worth a separate look, since a suite that passes alone and fails together is a real footgun.