Staleness-aware median pricing with source fallback

[Miracle656]

Background

A single price source can go stale or wrong. A median across sources with explicit staleness handling produces a robust price (distinct from a per-source confidence score).

What to build

Aggregate multiple sources into a median, drop sources older than a freshness threshold, and fall back through a priority chain when too few fresh sources remain — annotating which sources contributed and which were excluded for staleness.

Key files

• src/pricing/median.ts (new)
• src/api/rest.ts

Acceptance criteria

• Median computed only from fresh sources
• Fallback chain engages when sources are stale/missing
• Response notes included vs excluded sources; unit tests

Drips Wave · Complexity: Advanced · 200 points

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[smith961]

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[fadesany]

@fadesany has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello maintainer, i would like to work on this issue

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