Support linear Resize in candle-onnx

[jesco-absolut]

Summary

Closes #3153.

This adds linear mode support for the 4D Resize operator in candle-onnx's simple_eval path.

• keeps the existing nearest path and its current constraints unchanged
• maps mode="linear" + coordinate_transformation_mode="half_pixel" to Tensor::upsample_bilinear2d(..., align_corners=false)
• maps mode="linear" + coordinate_transformation_mode="align_corners" to Tensor::upsample_bilinear2d(..., align_corners=true)
• continues to reject unsupported linear coordinate transformation modes explicitly

Tests

Added focused ONNX op tests in candle-onnx/tests/ops.rs for:

• Resize with mode="linear" and coordinate_transformation_mode="half_pixel"
• Resize with mode="linear" and coordinate_transformation_mode="align_corners"

Before the source change, the half_pixel regression test failed with:

Unsupported resize mode: linear

After the change, the focused resize tests pass.

Validation

Passed:

cargo test --manifest-path candle-onnx/Cargo.toml --test ops resize_linear
cargo test --manifest-path candle-onnx/Cargo.toml --test ops -- --skip test_gelu_operation
cargo test --manifest-path candle-onnx/Cargo.toml --lib
cargo fmt --manifest-path candle-onnx/Cargo.toml -- --check
git --no-pager diff --check

Notes:

• cargo test --manifest-path candle-onnx/Cargo.toml currently fails in unrelated test_gelu_operation due exact float equality (0.8413447 vs 0.8413448).
• cargo clippy --manifest-path candle-onnx/Cargo.toml --tests -- -D warnings is currently blocked by pre-existing generated-code/test lints in candle-onnx, not by this patch.

Blast radius

This only changes the Resize arm in candle-onnx/src/eval.rs.

Existing nearest behavior remains constrained to the previous supported path (nearest_mode="floor", coordinate_transformation_mode="asymmetric"). The new behavior is limited to 4D linear resize using Candle's existing bilinear resize primitive.