Edit opacity from 0.8 to 0.5 and remove forBackdropFilter (#5291)

Update for #4836 

- edit primary and secondary transparency opacities from 0.8 to 0.5
- remove forBackdropFilter from themes
- update components referencing transparency/primary and
transparency/secondary to have the following backdrop-filter: blur(12px)
saturate(200%) contrast(50%) brightness(130%)

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Co-authored-by: Félix Malfait <felix.malfait@gmail.com>

packages/twenty-front/src/modules/ui/input/button/components/FloatingIconButton.tsx

@@ -30,7 +30,10 @@ const StyledButton = styled.button<
   >
 >`
   align-items: center;
-  backdrop-filter: ${({ applyBlur }) => (applyBlur ? 'blur(20px)' : 'none')};
+  backdrop-filter: ${({ applyBlur }) =>
+    applyBlur
+      ? 'blur(12px) saturate(200%) contrast(50%) brightness(130%)'
+      : 'none'};
   background: ${({ theme, isActive }) =>
     isActive ? theme.background.transparent.medium : theme.background.primary};
   border: ${({ focus, theme }) =>