docs: updates to zksync os dev preview (#443)

Updates to ZKsync OS dev preview docs:

- adds an faq question about pre-deployed contracts
- adds a link to the network details page on the quickstart
- adds foundry quickstart
- adds portal link

Author: sarahschwartz

content/00.zksync-network/65.zksync-os/05.network-details.md

@@ -35,8 +35,8 @@ You can get testnet funds from one of many [testnet faucets](/zksync-network/eco
 
 ### Bridging testnet ETH
 
-The ZKsync portal is not yet updated to support ZKsync OS.
-Until then, you can use `cast` or `zksync-sdk` to manually bridge funds over as shown in the examples below:
+You can use the [ZKsync OS Portal](https://zksync-os.portal.zksync.io/) to bridge testnet ETH over to the devnet.
+You can also use `cast` or `zksync-sdk` as shown in the examples below.
 
 #### Bridging with `cast`
 
@@ -55,6 +55,6 @@ export VALUE_TO_BRIDGE=<AMOUNT_TO_BRIDGE_IN_WEI>
 cast send -r $SEPOLIA_RPC $BRIDGEHUB_ADDRESS "requestL2TransactionDirect((uint256,uint256,address,uint256,bytes,uint256,uint256,bytes[],address))" "($CHAIN_ID,$VALUE_TO_BRIDGE,$ADDRESS,50,0x,300000,800,[],$ADDRESS)" --value $VALUE_TO_BRIDGE --private-key=$PRIVATE_KEY
 ```
 
-#### Bridging with `@zksync-sdk`
+#### Bridging with `zksync-sdk`
 
-You can find examples for bridging with `ethers` or `viem` in the [`@zksync-sdk` docs](https://dutterbutter.github.io/zksync-sdk/overview/index.html).
+You can find examples for bridging with `ethers` or `viem` in the [`zksync-sdk` docs](https://dutterbutter.github.io/zksync-sdk/overview/index.html).

content/00.zksync-network/65.zksync-os/07.quickstart.md

@@ -4,17 +4,22 @@ description: Getting starting developing with ZKsync OS
 ---
 
 You can use all standard EVM tooling for ZKsync OS.
+You can find instructions for bridging testnet ETH to ZKsync OS devnet in the [Network Details](/zksync-network/zksync-os/network-details) page.
 
-To get started with Hardhat, follow the steps below:
+To get started with Foundry or Hardhat, follow the steps below:
 
 ::content-switcher
 ---
 items: [{
+  label: 'Foundry',
+  partial: '_partials/_foundry'
+}, {
   label: 'Hardhat 3 with Viem',
   partial: '_partials/_viem'
 }, {
   label: 'Hardhat 3 with Ethers',
   partial: '_partials/_ethers'
-}]
+},
+]
 ---
 ::

content/00.zksync-network/65.zksync-os/10.faqs.md

@@ -30,6 +30,7 @@ Like with other EVM equivalent L2 solutions, there are a few distinctions that a
   For app developers this only affects storage proofs.
   More details about the storage model can be found in the [`zksync-os` repository](https://github.com/matter-labs/zksync-os/blob/main/docs/system/io/io.md).
 - Blake2f (`0x09`) and KZG point evaluation (`0x0a`) precompiles are not yet supported.
+- Priority fees do not yet affect the priority of transactions.
 
 ## Is ZKsync OS replacing EraVM? Will existing chains upgrade to it?
 
@@ -79,3 +80,8 @@ Currently there is no public mainnet.
 
 Running a ZKsync OS chain is not yet supported using `zkstack`.
 A full guide for running a ZKsync OS chain will be available soon.
+
+## Are there pre-deployed contracts?
+
+Yes, all [pre-deployed contracts](/zksync-protocol/evm-interpreter/pre-deployed-contracts)
+that were available on EraVM with the exceptions of the Create2 Deployer and Safe contracts are available.

content/00.zksync-network/65.zksync-os/_partials/_foundry.md

@@ -0,0 +1,45 @@
+---
+title: Foundry
+---
+
+1. Create a new foundry project:
+
+    ```bash
+    forge init Counter
+    cd Counter
+    ```
+
+1. Build the project
+
+    ```bash
+    forge build
+    ```
+
+1. Set your private key for deploying:
+
+    ```bash
+    export TESTNET_PRIVATE_KEY="0x..."
+    ```
+
+1. Deploy the contract:
+
+    ```bash
+    forge script script/Counter.s.sol --rpc-url https://zksync-os-testnet-alpha.zksync.dev --broadcast --private-key $TESTNET_PRIVATE_KEY
+    ```
+
+1. Set the number value:
+
+    ```bash
+    cast send 0xCA1386680bfd9D89c7cc6Fc3ba11938ba6E44fef \
+    "setNumber(uint256)" 5 \
+    --rpc-url https://zksync-os-testnet-alpha.zksync.dev \
+    --private-key $TESTNET_PRIVATE_KEY
+    ```
+
+1. Get the latest number value:
+
+    ```bash
+    cast call 0xCA1386680bfd9D89c7cc6Fc3ba11938ba6E44fef \
+    "number()" \
+    --rpc-url https://zksync-os-testnet-alpha.zksync.dev
+    ```