[WIP] Add bytes strict type to parametrized functions

[kramstrom]

Describe your changes

Do not merge -- need to merge backend support before this.

Adds support for new strict bytes type for modal.parameter

Usage:

@app.cls()
class C:
    a: bytes = modal.parameter(default=b"hello")

• Provide Linear issue reference (e.g. MOD-1234) if available.

Backward/forward compatibility checks

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Check these boxes or delete any item (or this section) if not relevant for this PR.

• Client+Server: this change is compatible with old servers
• Client forward compatibility: this change ensures client can accept data intended for later versions of itself

Note on protobuf: protobuf message changes in one place may have impact to
multiple entities (client, server, worker, database). See points above.

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Changelog

Adds support for new strict bytes type for modal.parameter

Usage:

import typing
import modal

app = modal.App()


@app.cls()
class Foo:
    a: bytes = modal.parameter(default=b"hello")

    @modal.method()
    def bar(self):
        return f"hello {self.a}"


@app.local_entrypoint()
def main():
    foo = Foo(a=b"world")
    foo.bar.remote()

For parameterized functions with web hooks you must base64 encode the bytes before passing them in as a parameter.

[kramstrom]

Need to merge the protos before merging this & merge the server-side code before this

[freider]

I think I found a bug, and a matching bug in the test that makes it pass :D

[freider]

this should return self.bar right? :D