feat(portal-provider): Add portal layer provider

[kunalpanchal]

Summary

Adds a ClickUI portal provider API for detached panels and other layered surfaces.

• Adds PortalProvider, usePortalContainer, and useResolvedPortalContainer
• Lets overlay components use an explicit provider container while preserving existing per-component container overrides
• Wires provider fallback through portal-based components including Select, Popover, Tooltip, Dropdown, AutoComplete, DatePicker, ContextMenu, HoverCard, Dialog, and Flyout
• Adds focused tests for provider placement and explicit container override
• Adds a minor changeset for the new public API

Context

This supports CUI-179 and avoids product code needing to target Radix internals or inject global z-index CSS for detached panels.

---

Note

Medium Risk
Touches portal mounting across many overlay components; wrong container choice could affect stacking, focus, or clipping in embedded panels, though behavior is backward-compatible when no provider is used.

Overview
Introduces PortalProvider and useResolvedPortalContainer so layered UI can default to a shared DOM mount point instead of only per-component Radix portals.

Wrap overlay Select, Popover, Tooltip, Dropdown, AutoComplete, DatePicker, ContextMenu, HoverCard, Dialog, and Flyout so their portal container comes from the provider when a content prop does not pass container explicitly; passing container on a component still wins. Tooltip gains a container prop on content (types moved to Tooltip.types.ts). The public package exports PortalProvider, usePortalContainer, useResolvedPortalContainer, and related types, with a minor changeset and integration tests for provider placement and override behavior.

^{Reviewed by Cursor Bugbot for commit 0902a00. Bugbot is set up for automated code reviews on this repo. Configure here.}

[changeset-bot]

🦋 Changeset detected

Latest commit: 0902a00

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@clickhouse/click-ui	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[workflow-authentication-public]

Storybook Preview Deployed

✅ Preview URL: https://click-4c0pg5ax5-clickhouse.vercel.app

Built from commit: f25115d199ec496b546adcc8cb43d21d81524f7e