fix(docs): remove undefined homepage icon class

[knqiufan]

Close #1178

Summary

• Remove the stale dynamic CSS Module lookup from homepage feature icon wrappers.
• Prevent the undefined CSS class token described in docs: homepage feature icons render a literal undefined class #1178 from being emitted in the homepage markup.

Test plan

• npm run typecheck
• Synced source docs and ran npm run build in a clean worktree.
• Confirmed the generated homepage HTML contains no undefined token.

[Teingi]

Thank you for your contribution! PowerMem has evolved into PowerContext as part of a major project upgrade, so we’re closing this PR for now. We truly appreciate your work and would be happy to revisit it in PowerContext if it is still relevant.