Add reorder_batch to TPU V1

[mgoin]

Before:

lm_eval --model vllm --model_args pretrained=Qwen/Qwen3-0.6B,max_model_len=2048 --trust_remote_code --tasks gsm8k --num_fewshot 5 --batch_size auto
Processed prompts: 100%|████████████████████████| 1319/1319 [00:53<00:00, 24.55it/s, est. speed input: 24370.56 toks/s, output: 2778.02 toks/s]
Running generate_until requests: 100%|██████████| 1319/1319 [00:53<00:00, 24.48it/s]
vllm (pretrained=Qwen/Qwen3-0.6B,max_model_len=2048,trust_remote_code=True), gen_kwargs: (None), limit: None, num_fewshot: 5, batch_size: auto
|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value |   |Stderr|
|-----|------:|----------------|-----:|-----------|---|-----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.4147|±  |0.0136|
|     |       |strict-match    |     5|exact_match|↑  |0.4170|±  |0.0136|

After:

lm_eval --model vllm --model_args pretrained=Qwen/Qwen3-0.6B,max_model_len=2048 --trust_remote_code --tasks gsm8k --num_fewshot 5 --batch_size auto
Processed prompts: 100%|████████████████████████| 1319/1319 [00:53<00:00, 24.50it/s, est. speed input: 24319.66 toks/s, output: 2772.22 toks/s]
Running generate_until requests: 100%|██████████| 1319/1319 [00:53<00:00, 24.43it/s]
vllm (pretrained=Qwen/Qwen3-0.6B,max_model_len=2048,trust_remote_code=True), gen_kwargs: (None), limit: None, num_fewshot: 5, batch_size: auto
|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value |   |Stderr|
|-----|------:|----------------|-----:|-----------|---|-----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.4147|±  |0.0136|
|     |       |strict-match    |     5|exact_match|↑  |0.4170|±  |0.0136|

[github-actions]

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[yarongmu-google]

@mgoin Our CI is now green - Chengji is on call this week :) Can we move forward now?

[yarongmu-google]

@yaochengji