feat: add onboarding walkthrough targets for dashboard widgets

[RajD2910]

Summary

This PR improves the onboarding walkthrough experience by adding target IDs to key dashboard widgets so the existing Driver.js onboarding tour can properly highlight and explain important sections of the dashboard.

Changes Made
Added onboarding tour target IDs for:
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Goals & Insights
Impact

These targets allow the onboarding walkthrough to spotlight and describe core dashboard sections, helping first-time users understand the available features and metrics.

Related Issue

Closes #2438

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