Deprecate pack (#6823)

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## PR-Codex overview
This PR focuses on deprecating the `Pack` contract in the `thirdweb` library due to its incompatibility with the Pectra update. Support for this contract will be removed in the next release.

### Detailed summary
- Added deprecation notice for the `Pack` contract in:
  - `packages/thirdweb/src/extensions/pack/createNewPack.ts`
  - `packages/thirdweb/src/extensions/prebuilts/deploy-pack.ts`

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Author: kumaryash90

.changeset/fluffy-bars-crash.md

@@ -0,0 +1,5 @@
+---
+"thirdweb": patch
+---
+
+Deprecate Pack

packages/thirdweb/src/extensions/pack/createNewPack.ts

@@ -78,6 +78,8 @@ export type CreateNewPackParams = {
 };
 
 /**
+ * * @deprecated [Pack contract is incompatible with Pectra update. Support for this contract is being removed in next release.]
+ *
  * @extension PACK
  * @example
  * ```ts

packages/thirdweb/src/extensions/prebuilts/deploy-pack.ts

@@ -55,6 +55,8 @@ export type DeployPackContractOptions = Prettify<
 >;
 
 /**
+ * @deprecated [Pack contract is incompatible with Pectra update. Support for this contract is being removed in next release.]
+ *
  * Deploy a thirdweb Pack contract
  * @param options params for deploying [`Pack contract`](https://thirdweb.com/thirdweb.eth/Pack)
  * @returns