[Feat] Feature: New Python-based Model Manager

[samzong]

Feature: New Python-based Model Manager

This PR introduces a new Python package model_manager to replace the previous Makefile-based model download logic. It converts projects from hard-coded shell scripts to configuration-driven Python applications.

🤔 Motivation (Context)

• Maintainability: The previous models.mk was becoming unwieldy with hardcoded lists of models and fragile shell logic. Adding a new model required modifying multiple conditional blocks.
• Reliability: Previous verification was minimal (sometimes just checking for a folder). The new system ensures files are actually readable and correct.
• Scalability: We needed better support for different "profiles" (Minimal CI vs Full Dev vs LoRA only), which is now naturally handled by swapping config files.

🚀 Changes:

• New model_manager Package src/model_manager.
• Config Driven: Models are now defined in
  • config/models.yaml (full)
  • config/models.minimal.yaml (CI)
  • config/models.lora.yaml (Lora)
• Atomic Caching: Uses a strict .downloaded marker + config check to ensure cached models are valid.
• Cross-Platform: Removes dependency on shell-specific logic for file downloading and verification.
• Refactored tools/make/models.mk Replaced complex if [ -f ... ] logic. But existing Makefile workflow is preserved.

FIX #xxxx (link existing issues this PR will resolve)
Part of #47

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[github-actions]

👥 vLLM Semantic Team Notification

The following members have been identified for the changed files in this PR and have been automatically assigned:

📁 config

Owners: @rootfs, @Xunzhuo
Files changed:

• config/models.lora.yaml
• config/models.minimal.yaml
• config/models.yaml

📁 src

Owners: @rootfs, @Xunzhuo, @wangchen615
Files changed:

• src/model_manager/__init__.py
• src/model_manager/__main__.py
• src/model_manager/cache.py
• src/model_manager/cli.py
• src/model_manager/config.py
• src/model_manager/downloader.py
• src/model_manager/errors.py
• src/model_manager/registry.py
• src/model_manager/requirements.txt
• src/model_manager/tests/__init__.py
• src/model_manager/tests/conftest.py
• src/model_manager/tests/test_cache.py
• src/model_manager/tests/test_cli.py
• src/model_manager/tests/test_downloader.py
• src/model_manager/tests/test_registry.py
• src/model_manager/tests/test_verifier.py
• src/model_manager/verifier.py

📁 tools

Owners: @yuluo-yx, @rootfs, @Xunzhuo
Files changed:

• tools/linter/codespell/.codespell.ignorewords
• tools/make/models.mk

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🎉 Thanks for your contributions!

This comment was automatically generated based on the OWNER files in the repository.

[rootfs]

@samzong this is great! thank you for making this happen!

[samzong]

@rootfs all changes is ready.

[JaredforReal]

@samzong LGTM, thanks! I am doing further work, including docs and concising config/ dir, and using model_manager dependencies (pip install -r src/model_manager/requirements.txt) instead of installing huggingface_hub[cli]] directly