fix(transaction-pay-controller, transaction-controller): support Predict same-chain withdraw on swap-only Relay routes

[dan437]

Explanation

Since the Polymarket pUSD migration on April 28 2026, Predict same-chain withdraws on Polygon (e.g. pUSD → USDC) sometimes fail with transaction gas limit too high (cap: 33554432, tx: 42121000).

Two interacting bugs:

1. transaction-pay-controller — calculateSourceNetworkCost always uses fromOverride = Safe proxy for Predict withdraws. That works for deposit-style Relay routes but breaks for the swap-aggregator routes that same-chain destinations now use post-migration: DEX aggregators reject contract callers (anti-MEV msg.sender == tx.origin checks etc.), so the swap step reverts in simulation.
2. transaction-controller — estimateGasBatch's 7702 path always calls estimateGas, even when every batch entry already has a gas value. The non-7702 path has had an allTransactionsHaveGas short-circuit since #7405; the 7702 path was missed. When TPC tries the EOA from, the swap sub-call reverts (EOA has no source token until the prepended Safe.execTransaction sub-call runs mid-batch), the whole 7702 batch falls back to ~block-gas-limit × buffer ≈ 42M, and Polygon's per-tx gascap rejects it.

Fix

• TPC relay-quotes.ts: gate fromOverride = Safe proxy on the route having a deposit step. Same-chain swap routes use the relay params' EOA from instead. Gas-fee-token lookup keeps using the Safe proxy (gated on isPredictWithdraw && refundTo) so the gasless flow still works for users with 0 POL.
• TPC constants.ts: add POLYGON_PUSD_ADDRESS and include it in STABLECOINS[Polygon] for correct stablecoin display.
• TC gas.ts: mirror the existing non-7702 short-circuit in the 7702 branch — when every transaction has a provided gas, sum them and skip simulation.

Verified end-to-end on mobile (yalc-linked): Polygon pUSD → USDC withdraw produces a sane fee both with POL and gasless (paid in pUSD). BNB cross-chain unchanged.

References

N/A

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 affect gas estimation and relay quote simulation paths for Predict withdraws, where subtle address-selection logic can impact fee calculation and transaction success on specific routes/chains.

Overview
Fixes Predict same-chain withdraws on swap-only Relay routes by avoiding Safe-proxy from overrides unless the quote includes a deposit step, while still using the Safe proxy for gas-fee-token lookup so gasless flows continue to work.

Updates TransactionController.estimateGasBatch to skip EIP-7702 simulation when all batch transactions already specify gas, via a new shared getProvidedBatchGasLimits helper, preventing fallback to near-block gas limits when sub-calls can’t be simulated standalone.

Adds Polygon Polymarket pUSD (POLYGON_PUSD_ADDRESS) to the stablecoin list for display/fiat-rate logic, and expands tests/changelogs to cover the new behaviors.

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