feat(icons): Add cloud-sync and cloud-backup

[ericfennis]

Closes #2055

Icon use case

From #2055:

Similar to the folder-sync icon the cloud sync would indicate a (two-way) sync with the cloud.
At the moment there are two cloud icons that either represent an upload or a download but no icon for both.

The use-case is that often one wants to sync information both ways (up and down) at the same time. This could be represented in two ways: either with an up and down arrow next to each other or -- like with the folder-sync -- a cloud and two arrows in a circle.

Alternative icon designs

See #2055

Icon Design Checklist

Concept

• I have provided valid use cases for each icon.
• I have not added any a brand or logo icon.
• I have not used any hate symbols.
• I have not included any religious or political imagery.

Author, credits & license

• The icons are solely my own creation.
• The icons were originally created in # by @
• I've based them on the following Lucide icons:
• I've based them on the following design:

Naming

• I've read and followed the naming conventions
• I've named icons by what they are rather than their use case.
• I've provided meta JSON files in icons/[iconName].json.

Design

• I've read and followed the icon design guidelines
• I've made sure that the icons look sharp on low DPI displays.
• I've made sure that the icons look consistent with the icon set in size, optical volume and density.
• I've made sure that the icons are visually centered.
• I've correctly optimized all icons to three points of precision.

Before Submitting

• I've read the Contribution Guidelines.
• I've checked if there was an existing PR that solves the same issue.

[github-actions]

Added or changed icons

Preview cohesion

Preview stroke widths

DPI Preview

16px (shadcn/ui)

24px (default)

32px (shadcn/ui + retina)

48px (default + retina)

Icon X-rays

Icon Diffs

Icons as code

Works for: lucide-react, lucide-react-native, lucide-preact, lucide-vue-next

const CloudBackupIcon = createLucideIcon('CloudBackup', [
  ["path",{"d":"M21 15.251A4.5 4.5 0 0 0 17.5 8h-1.79A7 7 0 1 0 3 13.607"}],
  ["path",{"d":"M7 11v4h4"}],
  ["path",{"d":"M8 19a5 5 0 0 0 9-3 4.5 4.5 0 0 0-4.5-4.5 4.82 4.82 0 0 0-3.41 1.41L7 15"}]
])

const CloudSyncIcon = createLucideIcon('CloudSync', [
  ["path",{"d":"m17 18-1.535 1.605a5 5 0 0 1-8-1.5"}],
  ["path",{"d":"M17 22v-4h-4"}],
  ["path",{"d":"M20.996 15.251A4.5 4.5 0 0 0 17.495 8h-1.79a7 7 0 1 0-12.709 5.607"}],
  ["path",{"d":"M7 10v4h4"}],
  ["path",{"d":"m7 14 1.535-1.605a5 5 0 0 1 8 1.5"}]
])

[ericfennis]

Not sure about the naming of the icons.
But I tried to be more in line with the other *-sync icons and database-backup.
Curious what you think.