feat: Add Web UI for AgentRed

[a805026135]

🌐 Add Web UI for AgentRed

This PR adds a Flask-based Web UI that allows users to run AgentRed security tests through a browser interface, making the tool much more accessible and user-friendly.

New Files

• web/app.py — Flask backend API (9 API endpoints + 2 page routes)
• web/templates/index.html — Test configuration & execution page (4 input modes, toggles, real-time progress, results display)
• web/templates/results.html — Historical reports page (score circles, risk badges, detail modal)
• web/static/favicon.svg — Website icon
• web/__init__.py — Module marker

Modified Files

• requirements.txt — Added flask>=3.0.0 dependency
• .gitignore — Added web/uploads/ for temporary upload files

Web UI Features

1. 4 Input Modes (tab switch): Local ZIP upload, Prompt input, API endpoint, Results JSON upload
2. 6 Feature Toggles (visual): Advisor, Config Checker, Tool Use, RAG/Memory Eval, Adaptive, Sanitized input
3. Real-time Progress: Progress bar + stage indicators + scrolling log output
4. Result Visualization: Score circle (color-coded by risk level), static/dynamic scores, recommendations
5. Historical Reports: Score sorting, risk level tags, detail modal, one-click download
6. 160 Test Cases Preview: Pagination + dimension/severity filters
7. Dark Red Theme: Matching AgentRed brand style
8. Health Check: Server status indicator (online/offline)
9. Toast Notifications: Differentiated error types (timeout, unreachable, non-JSON response)
10. Input Validation: Missing file/text prompts before sending empty requests

Start Command

python -m web.app --port 5000

Key Bug Fixes

• LogCapture instead of builtins.print — Prevents Flask server crash from global print replacement
• Global JSON error handlers — 400/404/413/500 all return JSON, not HTML error pages
• 50MB upload limit — Supports larger agent packages
• Safe ZIP extraction — Prevents path traversal attacks