chore(ci): update lit migration agent (v2)

[y-lakhdar]

The previous agent created the tests for the snapshots but never ran the tests

[Copilot]

Pull request overview

This PR enhances the Stencil-to-Lit migration agent documentation by making the visual regression testing workflow more explicit and actionable. The update addresses an issue where the agent would create visual tests but fail to actually run them and verify the results before proceeding with migration.

Key changes:

• Restructured Step 0 with explicit sub-steps (build, generate, verify, commit) to ensure snapshots are actually created and committed before migration
• Added verification commands and checkpoints to confirm snapshots exist and are included in git commits
• Enhanced instructions to update page object imports from base-page-object to lit-base-page-object during migration
• Removed redundant "What's New in V2" section while preserving all critical information in detailed workflow sections

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[Copilot]

Inconsistent working directory assumption. In Step 0.4 (line 190), the instructions say cd packages/atomic, and Step 0.5 uses a relative path (src/components/**/e2e/__snapshots__/*.png), implying the user is still in the packages/atomic directory. However, this step uses an absolute path from the repository root (packages/atomic/src/components/**/e2e/).

Either:

1. Use src/components/**/e2e/ (relative to packages/atomic)
2. Or add a command to return to repository root first: cd ../..