Distinguish modest quote delays from stale-price attention #163

Problem

A quote slightly beyond the 20-minute freshness boundary appears as an actionable stale-price problem. The last known price is available, but Needs attention makes a normal delayed observation look like missing account data.

Steps to reproduce

1. Load a reconciled market-priced holding with a valid quote timestamp 26 minutes before the response.
2. The read correctly marks the quote stale for strict daily-return coverage.
3. Holdings and detail display an undifferentiated stale warning and Needs attention asks the user to retry.

Expected behavior

Display modest delays beside the price, including source time/age, while preserving the last known value. Only genuinely old, undated or unavailable quotes need stronger attention. Preserve API/MCP financial freshness rules and unavailable Today returns.

Acceptance criteria

• Known stale quotes no more than one hour old show Delayed price with age/source timestamp, without stale-price Needs attention.
• Older, invalid or missing timestamps and missing prices preserve actionable warnings; other purchase/FX/position warnings remain independent.
• Holding details use the same presentation; privacy and source timestamps remain intact.
• Client regressions and checks pass; existing local financial facts are unchanged.

Context or visuals

Under #123. Related pending dividend fix #161 / PR #162. This is presentation only: no extension of the 20-minute calculation threshold, provider/cache changes, migrations or financial writes.