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# Motivation

The NIO 2.78 release introduced a bunch of new warnings. These warnings
cause us a bunch of trouble, so we should fix them.

# Modifications

Mostly use a bunch of assumeIsolated() and syncOperations.

# Result 

CI passes again.

Note that Swift 6 has _many_ more warnings than this, but we expect more
to come and we aren't using warnings-as-errors on that mode at the
moment. We'll be cleaning that up soon.

This PR adds support for Android, mostly just by importing the Android
module when needed.

### Motivation:

In some cases we can crash because of a precondition failure when the
write timeout fires and we aren't in the running state. This can happen
for example if the connection is closed whilst the write timer is
active.

### Modifications:

* Remove the precondition and instead take no action if the timeout
fires outside of the running state. Instead we take a new `Action`,
`.noAction` when the timer fires.
* Clear write timeouts upon request completion. When a request completes
we have no use for the idle write timer, we clear the read timer and we
should clear the write one too.

### Result:

Fewer crashes.

The supplied tests fails without these changes and passes with either of them.