Add `IntoPyObject` conversion trait #10677

Job	Run time
fmt	16s
resolve	7s
semver-checks	18s
clippy/aarch64-apple-darwin/stable	7m 56s
clippy/x86_64-unknown-linux-gnu/stable	13m 36s
python${{ matrix.python-version }}-${{ matrix.platform.python-architecture }} ${{ matrix.platform.os }} rust-${{ matrix.rust }}	0s
clippy/powerpc64le-unknown-linux-gnu/stable	12m 45s
check-msrv	10m 39s
careful	0s
clippy/s390x-unknown-linux-gnu/stable	12m 53s
coverage windows-latest	8s
clippy/wasm32-wasi/stable	12m 31s
coverage macos-14	7s
clippy/x86_64-pc-windows-msvc/stable	19m 32s
docsrs	0s
coverage ubuntu-latest	11m 11s
clippy/i686-pc-windows-msvc/stable	17m 31s
valgrind	0s
clippy/x86_64-unknown-linux-gnu/beta	13m 13s
check-feature-powerset ${{ matrix.rust }}	0s
emscripten	0s
test-cross-compilation ${{ matrix.os }} -> ${{ matrix.target }}	0s
test-cross-compilation-windows	0s
test-debug	0s
test-version-limits	0s
python3.12-x64 ubuntu-latest rust-nightly / build	3m 28s
python3.12-x64 macos-13 rust-stable / build	11m 32s
python3.12-arm64 macos-14 rust-stable / build	5m 27s
python3.12-x64 ubuntu-latest rust-stable / build	9m 5s
python3.12-x64 windows-latest rust-stable / build	14m 10s
python3.12-x86 windows-latest rust-stable / build	11m 1s
conclusion	1s
	3h 7m 27s

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