feat: add Drawer component

[hervedombya]

Summary

• Adds a Drawer component: a slide-in panel that can open from any edge (left/right/top/bottom)
• Supports optional overlay backdrop, configurable size, footer slot, and Escape key to close
• Renders via portal (same pattern as Modal) with dedicated drawer zIndex (8200, between overlay and modal)

Context

Needed by the Data Browser theme customization feature (DBR-4) as the container for the branding editor panel.

Ref: https://scality.atlassian.net/browse/CUI-10

[bert-e]

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[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• one peer

Peer approvals must include at least 1 approval from the following list:

• @damiengillesscality

• @hervedombya

• @JeanMarcMilletScality

• @MonPote

• @ChengYanJin

• @JBWatenbergScality

• @ZiyangLinScality

[Cuervino]

1. I'm not sure about what bgColor, I would do the same as a Modal or a page for the title / content / footer.
2. Save button should be larger, maybe it's a button min-width.
3. Maybe a border on the side?
4. I like the shadow effect.

[JeanMarcMilletScality]

I found an issue with the close button. It is still focusable while the drawer is closed (using keyboard) 👇

[hervedombya]

1. I'm not sure about what bgColor, I would do the same as a Modal or a page for the title / content / footer.
2. Save button should be larger, maybe it's a button min-width.
3. Maybe a border on the side?
4. I like the shadow effect.

1. Align background colors with Modal: header=backgroundLevel3, body=backgroundLevel4, footer=backgroundLevel3
2. Added minWidth for storybook stories
3. Added 1px solid border on the side facing the content
4. 👍

[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• one peer

Peer approvals must include at least 1 approval from the following list:

• @hervedombya

• @JeanMarcMilletScality

• @MonPote

• @JBWatenbergScality

• @ChengYanJin

• @ZiyangLinScality

• @damiengillesscality

[hervedombya]

/approve

[bert-e]

I have successfully merged the changeset of this pull request
into targetted development branches:

• ✔️ development/1.0

Please check the status of the associated issue CUI-10.

Goodbye hervedombya.

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