Revise bridge contract details and add addresses

[uF4No]

Description

Updated bridge contract descriptions and added new bridge addresses.

Issue(s) fixed

N/A - Bridges were updated on ZKsync a while ago and legacy ones are being deprecated. See this announcement

Fixes #2928

Preview

Checklist

• If this PR updates or adds documentation content that changes or adds technical meaning, it has received an approval from an engineer or DevRel from the relevant team.
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Note

Low Risk
Documentation-only change to RPC reference text and sample addresses; no runtime or API implementation changes.

Overview
Updates zks_getBridgeContracts reference docs so the Response section matches ZKsync’s current bridge layout: l1Erc20DefaultBridge is described as the legacy L1 ERC-20 bridge, and three fields are added—l1SharedDefaultBridge, l2LegacySharedBridge, and l2SharedDefaultBridge—with short descriptions for L1/L2 asset bridging.

The example JSON response is expanded from two bridge addresses to five, including new mainnet-style addresses and moving the former l2Erc20DefaultBridge example value onto l2LegacySharedBridge.

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[vercel]

@uF4No is attempting to deploy a commit to the Consensys Team on Vercel.

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[yashovardhan]

The response I receive from zks_getBridgeContracts for both the providers we have:
{
"jsonrpc": "2.0",
"id": 1,
"result": {
"l1SharedDefaultBridge": "0x8829ad80e425c646dab305381ff105169feece56",
"l2SharedDefaultBridge": "0x0000000000000000000000000000000000010003",
"l1Erc20DefaultBridge": "0x57891966931eb4bb6fb81430e6ce0a03aabde063",
"l2Erc20DefaultBridge": "0x0000000000000000000000000000000000010003",
"l1WethBridge": "0x0000000000000000000000000000000000000000",
"l2WethBridge": "0x0000000000000000000000000000000000000000",
"l2LegacySharedBridge": "0x11f943b2c77b743ab90f4a0ae7d5a4e7fca3e102"
}
}This matches the addresses that you added to the docs.

Thanks for your contribution