fix(core-backend): price supportedNetwork response

[Kriys94]

Explanation

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Medium Risk
Breaking TypeScript shape for supported-networks responses affects downstream consumers, while the PriceDataSource fix changes which chains get v3 price requests (restores pricing on v3-partial networks, avoids incorrect inclusion from v2-only lists).

Overview
Aligns core-backend Price API types with the real /v1 and /v2/supportedNetworks payloads: partialSupport is no longer a flat string[] but an object keyed by spot-price endpoint (spotPricesV2, and for v2 also spotPricesV3). Adds PriceV1SupportedNetworksResponse and PriceV2SupportedNetworksResponse, wires them through PricesApiClient, exports, tests, and README; PriceSupportedNetworksResponse is deprecated (still aliased to the v2 type for compatibility).

PriceDataSource no longer treats object-shaped partialSupport like an array when building the supported-chain set for /v3/spot-prices. It now uses fullSupport + partialSupport.spotPricesV3, ignores v2-only partial chains, and still accepts a legacy array-shaped partialSupport as a fallback. Tests and mocks were updated accordingly (including human-readable balance fixtures in price tests).

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[Prithpal-Sooriya]

lol I remember now 😄