Remove no exp usage from logical rule 1/N

[NuojCheng]

Description

This PR deprecates

• activation_batch_no_exp
• activation_length_no_exp

from logical names.

After this change

• activation_batch always includes "expert" physical axis
• activation_batch_moe does not include "expert"
• activation_length does not include "expert"

Other logical names containing "_no_exp" will be deprecated in following PR.

Tests

Please describe how you tested this change, and include any instructions and/or
commands to reproduce.

Checklist

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• I have made or will make corresponding changes to the doc if needed, including adding new documentation pages to the relevant Table of Contents (toctree directive) as explained in our documentation.

[codecov]

Codecov Report

❌ Patch coverage is 90.90909% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/maxtext/layers/decoders.py	66.66%	1 Missing ⚠️
src/maxtext/layers/nnx_decoders.py	50.00%	1 Missing ⚠️

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[RissyRan]

Could you help check if this breaks inference workflow? Potentially this has been deprecated due to vLLM migration.

[NuojCheng]

Could you help check if this breaks inference workflow? Potentially this has been deprecated due to vLLM migration.

AFAIK inference.yml is deprecated. I will check inference path in https://github.com/AI-Hypercomputer/maxtext/blob/main/src/maxtext/configs/inference/vllm.yml.