[UI/UX] Highlight edited service entries

[gacarrillor]

Fix #23

vokoscreenNG-2024-05-02_16-57-39.mp4

Features:

• Edited entry is highlighted in red and italics.
• An edited entry leads to enable the Update service button.
• Reedited values that return to their original stored value, go back to initial state (black and no italics). If the reedited value makes all values correspond to their original state, the Update service button is disabled, since there's nothing to save.
• Once edited values are saved, they go back to initial state (black and no italics) and the Update service button gets disabled.

[gacarrillor]

@3nids, please help me testing this PR.

BTW, isn't red a bit too strong for users? It might convey the message that something is wrong with the new value.
Do you know if we use this approach elsewhere in QGIS?

[3nids]

Yep, you're right, maybe blue or green would be more appropriate.

[gacarrillor]

Yep, you're right, maybe blue or green would be more appropriate.

Let's set it to dark green then (normal green was too light).