feat(py-client): Add automatic resumable uploads

[lcian]

Session.put now automatically uses resumable uploads under the hood for eligible uploads. An upload is eligible if:

• Its known remaining source size is at least resumable_threshold_bytes (default 32 MiB), measured before any compression
• It's a bytes buffer or a seekable stream
  • If it's a stream, it doesn't need on-the-fly compression (so either it needs no compression at all, or is precompressed)

We could later extend this to streams that need compression but that means we'll need a "staging area" either on disk or in memory to hold the compressed version, so that requires some more thought.
The same mechanism could be used if the stream is non-rewindable to make it rewindable, though I'm not sure that's something we want to do.

Usecase gains the following kwargs, shown with their defaults:

Usecase(
    "debug_files",
    resumable_threshold_bytes=32 * 1024 * 1024,   # ``None`` disables resumables
    resumable_retries=objectstore_client.ResumableRetryPolicy(
        retries=2,   # ``retries = 0`` disables resumables
        delay=2.0,
        jitter=1.0
    ),
)

Session.put also gains resumable_threshold_bytes for per-request overrides, defaulting to the value set on the Usecase.

The reason why I decided to make resumable_retries configurable is because we already make the urllib3 retry policy configurable, and resumable requests actually honor it, overriding just whole-body retries with our own logic.
Introducing such behavior with a non-overridable default doesn't seem like a good option to me.

Closes FS-389

[linear-code]

FS-389

[cursor]

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