feat: add project scan history page and link from supported projects list

[igor-soldev]

Summary

This PR reverts the experimental tile/showcase grid layout and returns to the original tabular view of the Supported Projects section. At the same time, it introduces a new long-awaited feature: a dedicated page showing the full scan history for a specific project.

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Changes

New: Project Scans View (project_scans.html)

A new template has been created that lists all audits performed for a given repository. The table includes:

• Scan date & time
• Grade (A–F)
• Total number of issues
• Scan source (e.g. Automated CI Scan, CLI Scan)
• A direct "View Report" link for each scan entry

Backend (app.py)

• Added GET /project-scans – renders the new HTML view, accepting a ?url=<repository_url> query parameter.
• Added GET /api/scans/project – API endpoint that searches through scan_results and returns a chronologically sorted list of all scans matching the given repository URL.

Updated: Supported Projects Table (supported_projects.html)

• Clicking a project name now navigates to its scan history page (/project-scans?url=...) instead of directly to GitHub.
• A discrete GitHub ↗ link is placed below the project name for direct access to the source repository.

UI Polish

• Replaced the large action-btn button style on "View Report" links with the lighter last-scan-link class for better visual consistency with the rest of the table UI.
• Unified the browser tab title format: {Project Name} Scans - InfraScan - Infrastructure Auditor Adoption Dashboard.

Reverted

• Removed the experimental showcase grid layout, generated cover images, and the manually curated showcase_projects.json data file.

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How to Test

1. Activate the virtual environment: source venv/bin/activate
2. Start the server: python3 app.py
3. Place sample scan result JSON files in the scan_results/ directory.
4. Navigate to the Supported Projects tab.
5. Click any project name in the table.
6. Verify you are redirected to /project-scans?url=... and that the table correctly displays the chronological scan history for that project.
7. Click View Report on any row and confirm it opens the correct scan report.