feat: remove all MYX protocol from core

[abretonc7s]

Explanation

@metamask/perps-controller shipped a full MYX protocol implementation alongside HyperLiquid and
Lighter. MYX is being dropped as a venue, and keeping it cost real weight: an optional
@myx-trade/sdk dependency, a dynamic-import + webpackIgnore workaround plus three
!dist/*MYX* files exclusions so extension bundles could skip the provider, and 'myx'
branches threaded through the controller, the provider router, and the provider-type unions.

This PR removes MYX from the package. It deletes MYXProvider, MYXClientService,
MYXWalletService, the MYX adapter, and the MYX config and type modules along with their test
suites; drops the @myx-trade/sdk dependency and the packaging exclusions it required; and
de-wires the controller — #isMYXProviderEnabled, the dynamic-import registration path,
registerMYXProvider, handleMYXImportError, resolveMyxAuthConfig, and the 'myx' routing and
cache-key branches all go. Net: ~8,700 lines removed across 42 files.

Notable API effects, all breaking for consumers that used MYX:

• PerpsProviderType is now 'hyperliquid' | 'lighter'. switchProvider('myx') returns
  { success: false, error: 'Provider myx not available' }. A 'myx' value restored from
  persisted state falls back to 'hyperliquid' and rewrites the persisted value, so existing
  MYX users self-heal on next launch rather than getting a broken perps tab.
• The MYXCredentials type and providerCredentials.myx option are gone.
• All MYX_* constants, getMYXChainId / getMYXHttpEndpoint, the fromMYX* / toMYX*
  converters, and the MYX-only USDT_BNB_TESTNET / USDT_BNB_MAINNET collateral addresses are no
  longer exported.
• PROVIDER_CONFIG.MYX_TESTNET_ONLY is removed; buildProviderCacheKey no longer special-cases
  'myx'.
• The perpsMyxProviderEnabled remote flag and MM_PERPS_MYX_PROVIDER_ENABLED env override are
  no longer read, so clients can retire both.

Two changes may not be obvious:

• packages/authenticated-user-storage is touched deliberately. PerpsWatchlistMarkets.myx
  is a server-persisted preference schema, not protocol code, and blobs already stored remotely
  contain a myx key. Deleting the required field would have failed validation on that existing
  data. It is instead made optional() and @deprecated: nothing writes it any more, stored
  blobs still validate, and perps-controller is left with zero MYX references.
• The files field is now plain ["dist/"]. With the MYX exclusions gone, everything emitted
  into dist/ publishes — so a stale dist/ from a previous build would ship MYX artifacts. The
  validation below uses yarn build:clean (which wipes packages/*/dist first) and asserts the
  emitted tree contains no MYX file at all.

HyperLiquid and Lighter behavior is unchanged. Where MYX served only as "a second provider" in
multi-provider aggregation, routing, and cache tests, those cases were repointed at Lighter rather
than deleted, so multi-provider coverage is preserved.

Validation

• yarn workspace @metamask/perps-controller run test — 79 suites, 3399 passed, 0 failures,
  coverage thresholds met (89.4% lines vs 80% required, 81.54% branches vs 69%, 85.58% functions
  vs 78%).
• yarn workspace @metamask/authenticated-user-storage run jest — 44 passed, 0 failures.
• yarn build:clean (root ts-bridge) — exit 0, "Project built successfully"; the emitted
  packages/perps-controller/dist contains no MYX file, and dist/index.d.cts / dist/index.cjs
  export no MYX symbol.
• ESLint over changed files — 0 errors. Prettier — clean. yarn changelog:validate — passes.
• An end-to-end proof recipe asserts the removal (no MYX in src//tests/, none in the manifest,
  none in the built dist/) and then reads live HyperLiquid testnet positions, orders, and
  account state through the de-wired controller to show the removal caused no regression. The
  assertions were confirmed to fail against the pre-change tree, so a revert of this diff breaks
  the recipe.

References

• https://consensyssoftware.atlassian.net/browse/TAT-3892

Client follow-ups needed before/alongside adoption:

• Mobile and extension must drop any providerCredentials.myx, activeProvider: 'myx', or
  providerId: 'myx' usage and remove MYX from provider pickers.
• The perpsMyxProviderEnabled remote feature flag can be retired once clients are updated.
• A future AUS schema migration can drop the deprecated myx watchlist key entirely once no
  stored blob relies on it.

Checklist

• I've updated the test suite for new or updated code as appropriate
  • MYX-only suites deleted; shared multi-provider tests repointed at Lighter so aggregation,
    routing, and cache coverage is preserved.
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
  • JSDoc examples that used 'myx' as a sample provider now use 'lighter'; comments in the
    Lighter provider, wallet service, and adapter that referenced MYX as their template were
    rewritten to stand alone.
• I've communicated my changes to consumers by updating changelogs for packages I've changed
  • perps-controller (Removed, **BREAKING:**) and authenticated-user-storage (Changed).
• I've introduced breaking changes in this PR and have prepared draft pull requests for
  clients and consumer packages to resolve them
  • Breaking changes are introduced and documented above, but the client draft PRs are not yet
    open. They are listed under References and should land before this is adopted.

Screenshots/Recordings

---

Note

Medium Risk
Large breaking removal across public types and exports; clients must drop MYX usage, though persisted stale provider state is handled with a HyperLiquid fallback.

Overview
Removes MYX as a perps venue across @metamask/perps-controller and aligned user-preference types. The MYX provider stack (MYXProvider, client/wallet services, adapters, config, types), the optional @myx-trade/sdk dependency, and dynamic-import / dist packaging workarounds are deleted (~8k+ lines).

Breaking API surface: PerpsProviderType is now 'hyperliquid' | 'lighter'; MYXCredentials, providerCredentials.myx, all MYX_* exports, and MYX-specific cache/config behavior are gone. The controller no longer registers MYX or reads perpsMyxProviderEnabled / MM_PERPS_MYX_PROVIDER_ENABLED. Persisted activeProvider: 'myx' self-heals to HyperLiquid instead of failing init. Multi-provider tests and docs examples that used MYX are repointed to Lighter.

Authenticated user storage: PerpsWatchlistMarkets drops the required myx key from types and validation; existing remote blobs with a myx field should still validate because unknown keys are ignored.

HyperLiquid and Lighter paths are otherwise unchanged.

^{Reviewed by Cursor Bugbot for commit 56a972d. Bugbot is set up for automated code reviews on this repo. Configure here.}

[abretonc7s]

Rebased onto origin/main (93d1ecb86) to clear the merge conflict — the PR was showing mergeable_state: dirty. Pushed as 56a972d11.

Two things needed resolving, both from main, neither from review feedback (there were no open review comments or unresolved threads on this PR):

1. packages/perps-controller/CHANGELOG.md conflict. main's #10021 entry and this PR's MYX-removal entry landed on the same ## [Unreleased] anchor. Kept both, ordered per Keep a Changelog (### Added, then ### Removed). Nothing dropped or reworded; yarn changelog:validate passes.

2. 'myx' came back via #10021's tests. The new Scale price-ladder tests use 'myx' as the stand-in second provider for routing cases. Since this PR removes 'myx' from PerpsProviderType, after the rebase those tests referenced a removed union member and the deleted mockMYXProvider. Git merged it textually with no conflict marker, so it only showed up as type errors.

Retargeted those cases at 'lighter', preserving each one's intent (default route, explicit route, not-implemented, not-registered, misattributed ladder). This matches the approach already used everywhere else in the PR — where MYX served only as "a second provider", the case was repointed at Lighter rather than deleted. Three test files touched, no src/ change:

• tests/src/providers/AggregatedPerpsProvider.test.ts
• tests/src/PerpsController.operations.test.ts
• tests/src/providers/HyperLiquidProvider.strategy-orders.test.ts

PerpsController.providers-cache.test.ts still contains the literal 'myx' on purpose — that's the regression test asserting init() self-heals a persisted activeProvider naming a removed venue. The literal is the assertion.

Validation on the post-rebase tree:

• perps-controller — 79/79 suites, 3417 passed, 0 failed; coverage 89.43% lines / 81.59% branches / 85.62% functions, all above thresholds.
• authenticated-user-storage — 44 passed, 0 failed.
• Root yarn build (ts-bridge) — exit 0, "Project built successfully". Emitted packages/perps-controller/dist contains zero MYX files and index.d.cts / index.cjs export zero MYX symbols (worth re-asserting since files is now plain ["dist/"]).
• ESLint on changed files — 0 errors. Prettier — clean. yarn changelog:validate — passes.
• The PR's proof recipe re-run post-rebase — pass: the removal assertions still hold, and the de-wired controller still reads live HyperLiquid testnet positions, orders, and account state.

Only the changelog needed a real merge decision; the rest was mechanical. Re-approval needed since the push reset it.