feat: multiple optimization profiles for disjoint input shape regimes

[cehongwang]

Add support for defining N optimization profiles at compile time via the list-based Input.profiles API and selecting the active profile at runtime (manual pin by index, or opt-in shape-based auto-selection).

• AOT (torch.export) compile path builds one TRT optimization profile per declared profile index; submodules inherit the profile count via propagation across graph breaks.
• Python and C++ runtimes expose a matching primitive engine API (set_active_profile / num_optimization_profiles / _active_profile_index / _auto_select_profiles) so the two runtimes remain interchangeable.
• Profile selection is exposed through the optimization_profile context manager; auto-selection uses lazy (first-fitting) profile selection.
• Backward compatible: engines without declared profiles keep the historical single-profile (dynamic) / no-profile (static) behavior.

Includes an example and runtime tests covering dynamic submodule inputs.

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

Type of change

Please delete options that are not relevant and/or add your own.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project (You can use the linters)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas and hacks
• I have made corresponding changes to the documentation
• I have added tests to verify my fix or my feature
• New and existing unit tests pass locally with my changes
• I have added the relevant labels to my PR in so that relevant reviewers are notified