Feature: Added music streaming activity with CO2 factor

[ZarrarPeshimam]

Description:

This PR introduces music streaming as a distinct activity type in the Carbon Tracker app. Users can now track their music consumption (Spotify, Apple Music, etc.) separately from video streaming, allowing for more accurate carbon footprint calculations and personalized reduction strategies.

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Close issue: #1

Changes Included:

• Added music_streaming to ActivityType in src/types/index.ts.
• Added CO₂ factor for music streaming: 8g per hour in src/constants/co2Factors.ts.
• Updated ActivityForm.tsx to include a form field for music streaming.
• Ensured the form UI is consistent with existing activity fields.
• Properly typed changes for TypeScript compatibility.

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Feature Details / Acceptance Criteria:

• Music streaming appears as a new activity option in the form.
• CO₂ calculations for music streaming work correctly.
• UI is consistent and fully functional.

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Demo:

bandicam.2025-10-21.11-35-58-204.mp4

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Reason / Problem Statement:

Previously, the app only tracked general streaming. Music streaming has a different carbon footprint compared to video streaming. Tracking it separately provides more granular insights into users’ digital carbon footprint.

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Notes / Next Steps:

• Adding music_streaming in weekly activity chart [beyond scope of allotted issue]
• Update any analytics or leaderboards if they include streaming activity breakdowns.

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@Eshaan-byte, Please review my PR as part of hacktoberfest

[ZarrarPeshimam]

@Eshaan-byte, Can u plz review my PR for hacktober?

[ZarrarPeshimam]

@Eshaan-byte, Can u plz review my PR?