feat(transaction-pay): add ordered strategy fallback orchestration

[pedronfigueiredo]

Explanation

As per preemptive validation on #7806

• Adds ordered strategy retrieval via TransactionPayController:getStrategies while preserving existing getStrategy behavior.
• Adds compatibility filtering (supports(...)) during strategy selection.
• Implements quote fallback orchestration:
  • try next strategy when quote retrieval fails
  • try next strategy when quote list is empty
  • skip unsupported strategies
• Implements publish-hook fallback orchestration:
  • execute primary strategy from existing quote strategy
  • on execution failure, rebuild quote requests and try next compatible strategy
  • throw original primary error if all fallback attempts fail

References

Addresses https://github.com/MetaMask/MetaMask-planning/issues/6992

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
Changes core quote selection/refresh and publish-hook execution paths, so strategy ordering and fallback behavior could alter which provider is used and when quotes clear/update, despite added unit coverage.

Overview
TransactionPayController now supports an ordered getStrategies callback (with validation) and falls back to a remote feature flag strategyOrder (defaulting to Relay) when callbacks are missing/invalid.

Quote retrieval is refactored to iterate strategies in order via getStrategiesByName, optionally skip incompatible strategies via new PayStrategy.supports, and automatically fall through to the next strategy when quotes are empty, quote fetching fails, or batch-transaction generation fails.

Quote refreshing and the publish hook are updated to carry/consume this strategy orchestration: refresh flows receive the strategy list provider, and TransactionPayPublishHook executes using the strategy encoded in the first stored quote rather than re-resolving strategy from the transaction. Tests/docs/changelog are updated accordingly.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

[matthewwalsh0]

Minor, alphabetical.

[matthewwalsh0]

Minor, if we're returning a single entry in the array, why do we need flatMap rather than map?

[matthewwalsh0]

Still confused by this type, wouldn't it just be TransactionPayStrategy[] and we get the first entry for the existing getStrategy messenger action?