chore: redesign with the dark theme

[pjuaristi-ikerlan]

Description

Redesign of the front end to use the dark theme.

Pre-review checks

Please ensure to do as many of the following checks as possible, before asking for committer review:

• DEPENDENCIES are up-to-date. Dash license tool. Committers can open IP issues for restricted libs.
• Copyright and license header are present on all affected files

[sonarqubecloud]

Quality Gate failed

Failed conditions
6.2% Duplication on New Code (required ≤ 3%)
C Reliability Rating on New Code (required ≥ A)

See analysis details on SonarQube Cloud

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