Add durable-specific serialization logic in the nodeJS worker

In [this](https://github.com/Azure/azure-functions-durable-js/issues/231#issuecomment-782288805) ticket, we learned that our string-serialization patch [here](https://github.com/Azure/azure-functions-durable-js/blob/c6e1844a3959fc37447c2a364ea0f8833a070852/src/utils.ts#L3) has broken some `function.json` functionality for some of our users.

The patch listed above was a minor "hack" in hopes to avoid changing the nodejs-worker's serialization logic, which could impact all of the JS azure functions infrastructure, not just durable. So while making serialization changes in the worker is often discouraged, in this case, since the new error manifests in a `function.json`, there's no fix we can implement at the Durable-level to get around this: a solution needs to be implemented in the worker.

To minimize impact and legacy behaviour across JS Functions, we can write durable-bindings-specific serialization and de-serialization logic in the worker.

The relevant files to modify are listed below:
* https://github.com/Azure/azure-functions-nodejs-worker/blob/617f3237e2683f2e3cc1e73847540537126ac190/src/FunctionInfo.ts#L34 [to assign a durable-specific encoder/decoder]
* https://github.com/Azure/azure-functions-nodejs-worker/blob/617f3237e2683f2e3cc1e73847540537126ac190/src/WorkerChannel.ts#L239 [to call the encoder]

Start by reviewing src/FunctionInfo.ts to understand where a durable-specific encoder and decoder would be assigned, then inspect src/WorkerChannel.ts around line 239 to see how the encoder is called. Done means durable bindings use their own serialization and deserialization path while existing JavaScript Functions behavior remains unchanged.

Written by the indexing model from the issue text.