perf: Directly provide payload to WASM entrypoints

[dima74]

Context

Fixes #5074

Solution

From the issue:

when wasm is executed it's entrypoint function is always without arguments and does a callback to get_xxx_context to initialize. We should remove that (as it saves us one call to host) and directly provide an encoded argument when calling the entrypoint function.

Checklist

• I've read CONTRIBUTING.md.
• (optional) I've written unit tests for the code changes.
• All review comments have been resolved.
• All CI checks pass.