feat: implement collapsible full-stack session history index to findi…

[SanjanaSAithal]

Description

This PR resolves the feature tracking a missing historical log view by introducing a full-stack, collapsible Session Index sidebar engine to the main Findings Desk layout. This allows security analysts to view, toggle, and dynamically hot-swap past scan data structures natively within the workspace panel.

Architectural Changes:

• Created a reusable ScanHistory.tsx component designed with a hard-edged geometric UI layout matching the project's styling system.
• Updated Findings.tsx to handle conditional rendering, sidebar constraints layout mapping, and integrated state persistence parameters.
• Implemented backend FastAPI routing changes to seamlessly inventory and deliver local output logs.

Related Issues

Closes #43

Type of Change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• Manual Pipeline Validation: Triggered local network diagnostics through the manual + TOOLKIT panel targeting 127.0.0.1 using the ICMP PING module.
• State Lifecycle & UI Verification: Verified that data dumps compile into backend/output/, load dynamically inside the collapsible Session Index module, and automatically scale the main findings view to full-width when hidden without layout wrapping issues.

Checklist

• My code follows the code style of this project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• My changes generate no new warnings.

[utksh1]

Requesting changes. CI formatting-hygiene is failing, so this cannot merge. Also the backend file is added as , outside the package where routes are currently registered, and the PR changes without a clear dependency reason. Please fix formatting, move/register backend code using the existing package structure if a backend endpoint is needed, remove unrelated lockfile churn, and add focused tests for the session-history behavior before re-review.

[utksh1]

Requesting changes. CI formatting-hygiene is failing, so this cannot merge. Also the backend file is added outside the backend/secuscan package where routes are currently registered, and the PR changes the frontend lockfile without a clear dependency reason. Please fix formatting, move/register backend code using the existing package structure if a backend endpoint is needed, remove unrelated lockfile churn, and add focused tests for the session-history behavior before re-review.