Exposing interleave argument for fused_apply_rotary_pos_emb_thd

[huvunvidia]

What does this PR do ?

Exposing interleave argument for fused_apply_rotary_pos_emb_thd.
This PR is the mirror of #3759.

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[ericharper]

/claude review

[claude]

Bug: The interleaved parameter is correctly passed in this if branch (TE >= 1.12.0), but the else branch at line 2596-2598 does not pass interleaved=interleaved to apply_rotary_pos_emb. This means on older TE versions, the interleaved setting will be silently ignored. Since this PR is specifically adding interleaved support, the fallback path should be fixed too:

# line 2596-2598, else branch:
return apply_rotary_pos_emb(
    t, freqs, tensor_format="thd", fused=True, cu_seqlens=cu_seqlens,
    interleaved=interleaved,
)

[jaredcasper]

If older TE versions don't have the interleaved argument we should assert False in the else branch.

[huvunvidia]

@jaredcasper I looked into the TE code and found out that interleaved only supports for TE>2.3.0.
Hence, I added a condition check for min_TE when using interleaved=True, if it's <2.3.0 will assert error. (https://github.com/huvunvidia/Megatron-LM/blob/ce883edd14063fa0f298b8b8bbaaea5f0ba893c9/megatron/core/extensions/transformer_engine.py#L2583)
With that we don't need to modify subsequent code.

[svcnvidia-nemo-ci]

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