feat(sdk-core): add abstract (chain 2741) v3 support

[gomesalexandre]

closes #377

what

adds Abstract (ZK-stack L2, chainId 2741) to sdk-core with its Uniswap V3 deployment. Abstract has V3 live per the gov RFC "Deploy Uniswap v3 on Abstract", but it's absent from sdk-core, so any SDK consumer can't resolve its contract addresses.

how

• chains.ts: ChainId.ABSTRACT = 2741, average block time (0.4), SUPPORTED_CHAINS
• addresses.ts: ABSTRACT_ADDRESSES (V3 only) + CHAIN_TO_ADDRESSES_MAP entry (the derived V3 maps pick it up automatically)
• tests in chains.test.ts + addresses.test.ts

the careful part: every address verified on-chain before inclusion

The issue proposed addresses marked "(to be verified)", and its V2 factory/router were Ethereum-mainnet placeholders (0x5C69…aA6f / 0x7a25…488D). Shipping wrong addresses in an SDK is how funds get lost, so I checked all of them against chain 2741 (https://api.mainnet.abs.xyz):

contract	address	check
v3CoreFactory	0xA1160e73B63F322ae88cC2d8E700833e71D0b2a1	deployed; feeAmountTickSpacing(500) = 10 ✅
swapRouter02	0x2cB10Ac97F2C3dAEDEaB7b72DbaEb681891f51B8	deployed; factory() → the v3CoreFactory ✅
nftPositionManager	0xfA928D3ABc512383b8E5E77edd2d5678696084F9	deployed; name() = "Uniswap V3 Positions NFT-V1", factory() → v3CoreFactory ✅
quoter	0x117Fc8DEf58147016f92bAE713533dDB828aBB7e	deployed; factory() → v3CoreFactory ✅
multicall	0x9CA4dcb2505fbf536F6c54AA0a77C79f4fBC35C0	deployed ✅
tickLens	0x9c7d30F93812f143b6Efa673DB8448EfCB9f747E	deployed ✅

V2 is omitted on purpose: the proposed V2 addresses have no bytecode on Abstract, and V2 was never in the RFC. 11 supported chains already ship no V2 factory (including ZKSYNC, the same ZK-stack family), so omitting is standard, not a gap.

Block time measured ~0.43s/block over 3000 blocks → 0.4.

receipts

$ cast chain-id --rpc-url https://api.mainnet.abs.xyz            → 2741
$ cast call <v3Factory>   "feeAmountTickSpacing(uint24)(int24)" 500   → 10
$ cast call <swapRouter02> "factory()(address)"                  → 0xA1160e73B63F322ae88cC2d8E700833e71D0b2a1
$ cast call <posManager>   "name()(string)"                      → "Uniswap V3 Positions NFT-V1"
$ cast call <posManager>   "factory()(address)"                  → 0xA1160e73B63F322ae88cC2d8E700833e71D0b2a1
$ cast code  <V2 factory placeholder>                            → 0x   (no code → omitted)

$ bun test    → 376 pass, 0 fail
$ bun run build → exit 0
$ eslint      → 0 warnings