user provided bound for torchtrt compile when export dimension is unb…

[apbose]

This PR validates user bounds against any finite exporter bounds, with three branches:

• Upper overflow (user_max > exp_max) → ValueError. TRT engine profile follows the exporter; shapes above exp_max would be rejected at runtime anyway.
• Lower underflow (user_min < exp_min) → ValueError, except the (user_min=1, exp_min=2) case which is just PyTorch's 0/1-specialization artifact (Dim(min=1) silently becomes 2 in ShapeEnv), this particular case emits a warning.
• Subset (user range strictly inside exporter range) → engine profile is narrowed to the user's bounds (logged at INFO). The user's Input(min_shape, max_shape) is the contract for the TRT profile; a subset of the exporter's valid range is still correct, and a tighter profile lets TRT specialize more aggressively.
• Dim.DYNAMIC (unbounded exporter upper) → no check, user fills the gap (the intended use).

[apbose]

CI index put cases failing. Looking at it.

[narendasan]

This PR is only for externally exported programs?

[apbose]

@narendasan yeah it addresses (torch_tensorrt.dynamo.compile(exported_program, ...)). The flow for torch_tensorrt.compile(model, inputs=..) should be unaffected, since in that case export bounds and input bounds should be same

[narendasan]

You should use the user bounds in the narrow case