Handle optional and network dependencies for tests

[beauagainagainagainagainagain]

Summary

• guard the wavelet denoising and sustainability dashboard modules so they import cleanly when PyWavelets, scikit-image, or Jinja2 are unavailable and fail fast with helpful messages when those features are invoked【F:digital_image_processing/wavelet_denoising.py†L1-L125】【F:sustainability/ctrl_compliance_dashboard.py†L20-L188】
• harden the anime fetcher and Instagram crawler with static user agents, graceful network error handling, and cached profile data for offline execution【F:web_programming/fetch_anime_and_play.py†L1-L167】【F:web_programming/instagram_crawler.py†L1-L182】
• extend the optional dependency test suite to exercise the new fallbacks and ensure they return predictable results under missing dependency or network failures【F:tests/test_optional_dependencies.py†L11-L161】

Testing

• pytest tests/test_optional_dependencies.py【3503e3†L1-L9】
• pytest【f8a5ca†L1-L62】

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https://chatgpt.com/codex/tasks/task_e_68d01ea2e97083209b38c5fd878370d0