feat: add Aptos chain support with NEAR Intents routing #12348

tl;dr

Add Aptos blockchain as a supported chain in ShapeShift Web, with NEAR Intents routing for cross-chain swaps into/out of APT and Aptos-native assets. Aptos is non-EVM (Move VM, BCS-signed transactions, Ed25519 + SHA3-256), so it follows the non-EVM chain integration pattern established by Solana, Sui, Near, Ton.

User-facing capabilities

• Connect a Native wallet that derives Aptos accounts at BIP44 m/44'/637'/0'/0'/0'
• View APT balance + Aptos-native asset balances in the portfolio
• Receive APT and any Aptos token (via address derivation + QR)
• Send APT and Aptos tokens (BCS-signed 0x1::aptos_account::transfer_coins)
• Swap into/out of APT and Aptos-native assets via NEAR Intents — cross-chain solver model (no APT needed on destination for incoming swaps; solver pays Aptos gas)

Scope (in this initial PR)

• HDWallet (Native): hdwallet-core Aptos interfaces + SLIP-44 637, hdwallet-native Ed25519 + SHA3-256 AptosAdapter (with mixins + native.ts init/wipe/describePath wiring)
• CAIP / chain adapter: full AptosChainAdapter (account discovery, balances, BCS signing, broadcast, fee estimation, 19 unit tests)
• App wire-up: Aptos plugin, feature flag VITE_FEATURE_APTOS, CSP headers, portfolio account derivation, send modal, trade execution dispatch, RFOX bridge integration, state migrations bump v334
• Asset data: ~80 Aptos tokens via the Panora token list, CoinGecko market data adapter, treasury / base assets
• NEAR Intents Aptos route: solver routing wired into NearIntentsSwapper for USDC / ETH / etc. ↔ APT and Aptos-native assets
• qabot fixture: e2e/fixtures/aptos-chain-integration.yaml for future automated regression
• Bug fix: Aptos fee estimation now uses sim.gas_used * 1.5 (Aptos CLI safety factor) instead of sim.max_gas_amount, which the node returns as the sender's affordability ceiling — fixes a 100-300× fee inflation on the trade preview

Not in scope (separate follow-up PRs)

• PanoraSwapper (Aptos-native DEX aggregator) — deferred to a stacked PR to keep this one reviewable
• External blockers (yield.xyz Aptos support, watchlists, etc.)

Risk

HIGH-RISK — introduces:

• A brand-new on-chain transaction type (BCS-signed Aptos SimpleTransaction.submit.simple)
• A new HDWallet implementation (Ed25519 + SHA3-256, SLIP-44 637) across hdwallet-core + hdwallet-native
• A new ChainAdapter (no code reuse from existing adapters)
• A new trade execution path + Send modal path
• NEAR Intents Aptos routing (extension of existing swapper — type ripple to AptosSwapperDeps requires updates in unrelated swapper test mocks, e.g. ButterSwap)
• State migrations bump (v334)

Risk is contained by feature flag: VITE_FEATURE_APTOS=false in .env.production. Operations testing follows the flag flip.

References

• .claude/contracts/second-class-evm-chain.md (contract — used as analog for non-EVM chain integration points)
• Aptos system integrators guide: https://aptos.dev/build/guides/system-integrators-guide
• Aptos TS SDK: https://aptos.dev/build/sdks/ts-sdk
• NEAR Intents documentation: https://docs.near-intents.org/