Refactor some auto splitter and linking code (LiveSplit#40)

This updates all of our dependencies, in particular `livesplit-core` now
uses the latest version of `wasmtime` again, it was stuck on an old
version. While updating I noticed that `hyperx` has upper bounds for all
of its dependencies, which made me rip out that dependency, which led me
to refactor a bunch of the auto splitting code. A lot more of the auto
splitting code now resides within that module, the error messages use
`anyhow` to build a nice chain of reasoning for the errors and removing
the `hyperx` crate forced me to modify retrieving the file name of the
downloaded files. The file names are now simply extracted from the URL,
which should honestly be fine. This should've been done as at least a
backup to the `Content-Disposition` header anyway. Maybe we can
eventually bring the `Content-Disposition` handling back.

Additionally, this now links against `OBS` differently on Windows. Rust
recently stabilized support for `raw-dylib`. On Windows you usually link
against `.lib` files, not against `.dll`s. Sometimes you may want to
link against a `.dll` however that you don't have a `.lib` file for.
With `raw-dylib` as the link type, you can now skip the `.lib` file
entirely on Windows and still link against a `.dll`. In fact, you still
don't need a `.dll`, so we can now skip building our fake `.dll` on
Windows entirely. We also don't need it anymore on macOS as we for now
link against the real framework provided by OBS there.

.github/workflows/build_shared.sh

@@ -18,11 +18,6 @@ main() {
         FEATURE_FLAGS="--no-default-features --features $FEATURES"
     fi
 
-    if [ "$OS_NAME" = "windows-latest" ]; then
-        $cargo build -p obs --target $TARGET $release_flag $FEATURE_FLAGS
-        cp target/$TARGET/$target_folder/obs.dll.lib ./obs.lib
-    fi
-
     $cargo build --target $TARGET $release_flag $FEATURE_FLAGS
 
     if [ "$OS_NAME" = "macOS-latest" ]; then