add foundry flatten script (#746)

Author: technophile-04

.changeset/wet-carrots-laugh.md

@@ -0,0 +1,5 @@
+---
+"create-eth": patch
+---
+
+forge flatten for foundy

templates/extensions/foundry/package.json

@@ -12,6 +12,7 @@
     "test": "yarn foundry:test",
     "verify": "yarn workspace @se-2/foundry verify",
     "generate": "yarn workspace @se-2/foundry generate",
+    "flatten": "yarn workspace @se-1/foundry flatten",
     "format": "yarn next:format && yarn foundry:format"
   }
 }

templates/extensions/foundry/packages/foundry/package.json

@@ -7,6 +7,7 @@
     "fork": "anvil --fork-url ${0:-mainnet} --chain-id 31337 --config-out localhost.json",
     "compile": "forge compile",
     "generate": "node script/generateAccount.js",
+    "flatten": "forge flatten",
     "deploy": "forge build --build-info --build-info-path out/build-info/ && forge script script/Deploy.s.sol --rpc-url ${1:-default_network} --broadcast --legacy && node script/generateTsAbis.js",
     "deploy:verify": "forge build --build-info --build-info-path out/build-info/ && forge script script/Deploy.s.sol --rpc-url ${1:-default_network} --broadcast --legacy --verify ; node script/generateTsAbis.js",
     "verify": "forge build --build-info --build-info-path out/build-info/ && forge script script/VerifyAll.s.sol --ffi --rpc-url ${1:-default_network}",