Add music category schema

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Goal

Add a music category schema for apps that understand listening preferences.

This should help Memact turn messy music-app context into user-readable Wiki entries that users can approve, edit, reject, or delete.

Context examples

Music apps may know things like:

• favorite genres
• disliked genres
• repeated artists
• skipped artists
• playlist themes
• listening moods
• discovery preferences
• explicit user preferences

Work to do

• Define useful context fields for the music category
• Add example raw app context dumps
• Add normalized context examples
• Add user-facing Wiki entry templates
• Mark sensitive or risky fields clearly
• Suggest category-level permissions apps should request
• Add tests for safe context shaping

Important product rule

Apps should propose context. Users control whether it becomes accepted memory.

Acceptance criteria

• A contributor can understand what music context is safe to store
• Raw app input examples exist
• Normalized output examples exist
• Wiki entry examples are human-readable
• Tests cover at least one valid and one unsafe/sensitive case

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Maintainer note for SSoC26 contributors:

Please comment before starting so work does not get duplicated. Keep the first PR small and focused.

For category schemas, apps should propose context; users control what becomes accepted memory. Prefer user-readable summaries over raw personal data, avoid sensitive trait inference, and do not write fake certainty.

Before opening a PR, read MEMACT.md and make sure your schema includes examples, Wiki entry outputs, permission suggestions, and at least basic tests.