feat(perps): add provider-routed Scale price normalization

[abretonc7s]

Explanation

Adds the provider-neutral PerpsController:getScalePriceLadder API. providerId is optional: omitting it uses the active/default provider, while supplying it routes explicitly in aggregated mode.

Providers own market metadata and venue formatting. HyperLiquid precision is no longer exposed through a public venue-specific helper.

References

• Related to feat(perps): add Scale orders to Pro mode metamask-mobile#35176
• Related to fix(perps): handle partial Scale order acceptance #9989
• Mobile follow-up: replace direct HyperLiquid formatting with this controller API after release

Validation

• Full @metamask/perps-controller suite and coverage gate
• 525 focused controller, aggregator, and HyperLiquid tests
• TypeScript, ESLint, Oxfmt, changelog validation, and messenger action generation
• Independent cross-model review approved bfe5e685c6e8c54fb46b8c446380e28bb1c6baa7

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 the Perps Controller changelog
• 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

Low Risk
Additive read-only API with optional provider hooks; HyperLiquid scale placement only shares an internal normalization helper, so trading behavior should stay consistent while previews move off client-side venue formatting.

Overview
Adds PerpsController:getScalePriceLadder so clients can preview Scale ladder prices through the same provider routing as order placement. Optional providerId selects a venue in aggregated mode; otherwise the active/default provider is used. Results are a ready payload with venue-normalized price strings or a typed unavailable status (mirroring order-capabilities reasons).

The PerpsProvider interface gains an optional getScalePriceLadder hook, with routing implemented on AggregatedPerpsProvider and a HyperLiquid implementation that resolves market szDecimals, formats rungs, and rejects ladders whose prices collapse to duplicates. HyperLiquid getOrderCapabilities is refactored to share market lookup with the ladder path, and scale placement reuses the same normalization helper so preview and submit stay aligned.

Exports messenger action types plus GetScalePriceLadderParams / PerpsScalePriceLadder; tests cover controller, aggregator, and HyperLiquid behavior.

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[geositta]

I reviewed this change against origin/main. Provider routing and Hyperliquid precision behavior are correct, and the shared normalizer keeps preview and placement formatting aligned. The two comments tighten TypeScript exhaustiveness and regression coverage without blocking this PR.

[geositta]

Could we define a Scale specific unavailable reason union? OrderCapabilitiesUnavailableReason includes strategy_market_unsupported, which this API cannot return and forces consumers to handle an impossible state.

[geositta]

Could we add a parity test comparing fractional preview prices with the prices submitted by Scale placement? Preview covers fractional prices, while placement assertions use integers; exact preview and submission parity is this API’s primary contract.