test: add unit tests for sensitive data masking (masker)

[tanmayjoddar]

Why

We rely on masking to ensure secrets never get written to disk. There are currently no tests for src/core/masker.js.

Scope

Add a Jest test file that covers key redaction + value-pattern redaction.

Where

• src/core/masker.js
• Add: tests/core/masker.test.js

Acceptance Criteria

• Tests cover redacting keys like token, password, secret, authorization, api_key
• Tests cover redacting JWT-like values and credit-card-like values
• Tests cover nested objects + arrays
• npm test passes

Notes

Current implementation mutates the input object; tests should reflect current behavior unless you decide to change it (then update callers accordingly).

[saurabhhhcodes]

Hi @tanmayjoddar, I would like to work on this under GSSoC'26.\n\nI will keep it focused on Jest coverage for src/core/masker.js: sensitive key redaction, JWT-like and credit-card-like value redaction, and nested object/array behavior while reflecting the current mutation semantics. I will run the full test suite before opening the PR.

[Tharsiga-21]

hi @tanmayjoddar can I work on this issue

[manya-singh7]

I'd like to be assigned to this. I am a GSSoC 2026 contributor. @tanmayjoddar