[Studio] Make group search case insensitive

[Aias00]

Summary

• normalize Consumer Group search text before filtering
• make group-name matching case-insensitive and ignore surrounding whitespace
• update page test coverage for uppercase search input

Verification

• npm --prefix web test -- --run src/pages/studio/tests/GroupManagement.test.tsx
• (cd web && npm exec eslint -- src/pages/studio/GroupManagement.tsx src/pages/studio/tests/GroupManagement.test.tsx)
• npm --prefix web run build

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[Aias00]

Superseded by #635. Folded into the consolidated service/search filter normalization PR to keep frontend and backend search normalization fixes in one review unit.