[feat] Standardize media handling and unify AgentOS routers

[nklowns]

Summary

fixes #7311 This PR standardizes media validation across the Agent platform by moving MIME type and extension checks into the core Media classes and simplifying the corresponding AgentOS routers.

Changes

Core Media Layer (libs/agno/agno/media.py):

• Added valid_mime_types() and valid_extensions() class methods to Image, Video, and FileMedia.
• Centralized validation logic to avoid hardcoded lists in routers.

AgentOS Routers (libs/agno/agno/os/routers/):

• agents/router.py & teams/router.py: Refactored file upload handling to use centralized media validation.
• Removed duplicated processing logic for images, videos, and documents.

Utilities & Normalization (libs/agno/agno/utils/common.py & libs/agno/agno/os/utils.py):

• Implemented case-insensitive MIME type normalization (e.g., IMAGE/PNG -> image/png).
• Added robust handling for special characters and emojis in filenames.

Tests:

• Added libs/agno/tests/unit/test_media_structure.py for core validation.
• Added libs/agno/tests/unit/os/test_utils_media.py for filename and normalization.
• Added E2E-style router tests in libs/agno/tests/unit/os/test_router_uploads.py.

Type of change

• Bug fix
• New feature
• Breaking change
• Improvement
• Model update
• Other:

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Checklist

• Code complies with style guidelines
• Ran format/validation scripts (./scripts/format.sh and ./scripts/validate.sh upward)
• Self-review completed
• Documentation updated (comments, docstrings)
• Examples and guides: Relevant cookbook examples have been included or updated (if applicable)
• Tested in clean environment
• Tests added/updated (if applicable)

Duplicate and AI-Generated PR Check

• I have searched existing open pull requests and confirmed that no other PR already addresses this issue
• If a similar PR exists, I have explained below why this PR is a better approach
• Check if this PR was entirely AI-generated (by Copilot, Claude Code, Cursor, etc.)

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Additional Notes

• Verified with 12 new unit tests covering SVG support, case-insensitivity, and filename encoding.
• Simplifies router maintenance by decoupling API logic from media validation rules.

[github-actions]

PR Triage

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