Add DanceAnon video anonymizer plugin

[Corgiac]

Problem

DanceAnon users need a reusable MiniMax Code workflow for checking the
environment, launching the Web application, running video anonymization,
troubleshooting models and ffmpeg, and making focused code changes.

Example prompt

Use the dance-anonymizer skill to check whether my local DanceAnon
project can start. Do not install or download anything yet.

Expected result

MiniMax Code locates the local DanceAnon checkout, checks Python,
dependencies, model checkpoints and ffmpeg, and reports missing
requirements before starting the application.

Dependencies and platforms

• Python 3.10+
• Local DanceAnon checkout
• Dependencies from requirements.txt
• YOLO, SAM2 and CUTIE model files required by DanceAnon
• ffmpeg when audio muxing is needed
• macOS, Windows and Linux

Network and data behavior

The Plugin itself performs no network requests and requires no account,
API key or paid service.

Network access is only needed when the user explicitly requests cloning,
package installation or model downloading.

Video files are processed locally by DanceAnon. The Plugin does not add
telemetry or upload videos.

Test evidence

• npm run validate: passed
• Plugin result: OK plugin Corgiac/dance-anonymizer
• npm run check: passed
• Node tests: 128 passed, 0 failed
• No TODO placeholders or personal absolute paths

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[hetaoBackend]

Current head bbc3292 was reviewed as a Skill-only plugin. The portable manifest and Skill validate, the package contains its README/project guide/MIT license, installation and model downloads require confirmation, input overwrite is prohibited, and no plugin-side network, credential, destructive-operation, or unsupported host-contract blocker was found. Full DanceAnon inference was not run because the external checkout and model weights are intentionally not bundled. [code]smith is SKIPPED.