docs: add beginner setup troubleshooting guide

[piyush10854]

📝 Summary of Changes

Added a beginner-friendly setup and troubleshooting guide to improve contributor onboarding for GSSoC 2026 participants.

This PR introduces a dedicated troubleshooting documentation section covering common setup issues faced by beginners while configuring the project locally.

The changes include:

• Python installation and virtual environment troubleshooting
• Node.js and npm setup guidance
• FFmpeg installation help
• Port conflict troubleshooting
• Dependency installation fixes
• Windows/Linux specific setup notes
• README update linking to the troubleshooting guide

These improvements help reduce repetitive setup questions and make the contribution process smoother for first-time contributors.

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🔍 Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📖 Documentation update
• 🧪 Test addition or improvement
• 🧹 Refactor / Code cleanup (no functional change)
• ⚙️ Build / CI / Chore

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🧪 How Was This Tested?

Verified:

• Markdown formatting renders correctly
• All commands and setup instructions are properly formatted
• README troubleshooting link works correctly
• File structure and documentation paths are valid

# Verified markdown and documentation structure manually

Test environment:

• OS: Windows 11
• Python version: 3.11
• Node version (if frontend): 20.x

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✅ Pre-Submission Checklist

• My branch is up to date with upstream/main
• My code follows the project's coding standards (Black, isort, flake8 pass)
• I have written/updated tests for my changes
• All existing tests pass (python -m pytest tests/)
• I have added docstrings and type hints to all new public functions
• I have updated relevant documentation (README, docs/, inline comments)
• My PR title follows the Conventional Commits format
• I have not committed any .env files, secrets, or model weights
• This PR addresses only the scope of the linked issue

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💬 Additional Notes for Reviewer

This PR focuses solely on improving beginner onboarding and the clarity of documentation for contributors participating in GSSoC 2026.

CLOSES #233