Rust

Remove CastColumnExpr and custom_file_casts example; unify on field-aware CastExpr #62919

Job	Run time
linux build test	2m 25s
build and run with wasm-pack	5m 10s
Verify Vendored Code	1m 17s
Check cargo fmt	1m 2s
Verify MSRV (Min Supported Rust Version)	5m 9s
cargo test (macos-aarch64)	13m 22s
cargo check datafusion-functions features	2m 28s
cargo check datafusion-substrait features	5m 44s
cargo test (amd64)	5m 38s
cargo test datafusion-cli (amd64)	3m 48s
cargo check datafusion features	8m 13s
cargo check datafusion-proto features	3m 3s
cargo check datafusion-common features	2m 2s
cargo doc	2m 43s
verify benchmark results (amd64)	7m 28s
cargo examples (amd64)	5m 11s
check Cargo.toml formatting	4m 48s
Run sqllogictest with Postgres runner	4m 13s
check configs.md and ***_functions.md is up-to-date	4m 22s
check example README is up-to-date	5m 54s
cargo test doc (amd64)	5m 43s
clippy	3m 52s
Run sqllogictest in Substrait round-trip mode	4m 38s
	1h 48m 13s

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