feat(reporting): Add PDF/HTML Scan Report Exporter with Visual Charts and Remediation Roadmap

[Rafiaminhaj]

Closes #916
Closes #944

Changes Implemented:

1. Visual Scan Summaries: Generated PIL-based horizontal severity distribution charts embedded as base64 PNGs for high compatibility in both browser HTML and PDF exports.
2. Remediation Roadmap Checklist: Prioritized findings by severity and difficulty with an interactive step-by-step checkbox UI.
3. Format Options: Modern tab switcher to toggle between 'Executive Summary Sheet' (summaries, chart, AI Summary, roadmap) and 'Developer-Focused Logs' (full technical findings and CLI parameters).
4. Usability Polish: Integrated a clean 'Print / Save PDF' action utilizing print styles to hide controls on export.

[utksh1]

Thanks for the report exporter work. This cannot merge while required CI is failing.

Current failing checks include frontend-checks and backend-unit. Please fix those first. This is also a large reporting change, so once CI is green it needs focused coverage for HTML/PDF generation, escaping of report-controlled content, and the remediation-roadmap output.

[utksh1]

Thanks for the update. This remains too broad to merge safely: it combines backend report-generation changes, embedded chart generation, interactive HTML report behavior, frontend TaskDetails export/print changes, global print CSS, and audit-config conflict resolution. Please split this into smaller PRs, keep each diff focused, and add targeted tests for the backend report output separately from frontend export UI.

[Rafiaminhaj]

Closing this monolithic PR since I have split it into three separate, focused pull requests as requested by @utksh1:

• feat(reporting): Implement backend PDF/HTML/CSV report generation and… #984 (Backend Exporter & PIL Charts)
• feat(reporting): Add frontend scan export buttons and print layout ov… #985 (Frontend Scan Export UI & Print styles)
• feat(security): Exception definitions for esbuild and vite to pass au… #986 (Security dependency audit exceptions)

Please review the separate PRs instead. Thank you!