[FRONTEND] Add WCAG audit fixes for scan configuration forms

[utksh1]

Problem

SecuScan needs a production-grade improvement in this area: Accessible dynamic plugin forms..

Scope

Audit labels, descriptions, error announcements, keyboard order, and focus management for Tool Config dynamic fields.

Acceptance Criteria

• The implementation is focused and does not introduce unrelated UI, docs, lockfile, or formatting churn.
• Security-sensitive behavior has explicit negative tests where applicable.
• Existing tests continue to pass, and new tests cover the main success and failure paths.
• Documentation or configuration examples are updated when operator behavior changes.

Verification

Tests should include axe checks plus keyboard interaction coverage for all field types.

Difficulty

Hard, useful issue intended for experienced contributors.

[SaumyaT-21]

Hello @utksh1 ! I'm a GSSoC '26 contributor. I some have experience building dynamic forms and would like to help make SecuScan's configuration more accessible by handling the WCAG audit and adding the required keyboard/axe tests. Could you please assign this to me?

[saurabhhhcodes]

I can take this one. I’ll keep it focused to frontend/src/pages/ToolConfig.tsx plus targeted frontend tests: improve labeling/description wiring for dynamic fields, tighten error announcements and invalid-field focus behavior, and add keyboard-oriented coverage for the dynamic field types without broad UI churn.

[saurabhhhcodes]

Opened PR #297 for this issue. It improves dynamic field accessibility in ToolConfig, adds first-invalid focus handling, preserves help + error descriptions together, and tightens button semantics/back navigation. I also added focused routing/dynamic-form test coverage updates.