[tech-debt] Narrow DashboardView unauthed tagline gating from `status !== 'authed'` to `status === 'unauthed'`

Follow-up from Wave 2a Cluster E1 (#221 About SIPHER tagline). Code-quality reviewer flagged the broad gating.

Current behavior

app/src/views/DashboardView.tsx:159 gates the unauthed tagline on status !== 'authed':

```tsx
{status !== 'authed' && (

Multi-chain privacy command center for shielded transfers across 9+ chains.

)} \`\`\`

This matches the spec text verbatim and is documented by an explicit test (DashboardView.test.tsx:175-183). But it also shows the tagline for:

• status === 'connecting' — transient flash of marketing copy while auth resolves
• status === 'expired' — returning user who knows what SIPHER is, the marketing pitch is wasted real-estate
• status === 'error' — auth error state, user probably doesn't want marketing copy mid-error

Proposed change

Narrow gating to status === 'unauthed' || status === 'error', OR just status === 'unauthed'.

Trade-off: brief tagline flash during initial auth connecting would disappear, slight UX improvement. Existing test at DashboardView.test.tsx:175-183 documents the current behavior — needs updating to assert the narrowed gating.

Decision needed

RECTOR call: accept current "fallback to pitch" UX, or narrow to unauthed only?

Source

Wave 2a Cluster E1 code-quality review minor finding #3.

Priority

Low — UX polish, not a regression.

Read app/src/views/DashboardView.tsx around line 159 and DashboardView.test.tsx around lines 175-183, then resolve the stated RECTOr decision about which auth states should show the tagline. Update the view and its explicit test to match the chosen gating, and run the DashboardView test to confirm all relevant states behave as intended.