fix(billing): portal usage popover

[hyrious]

Summary

• Render the plan and usage popover through the shared Radix Popover portal so the titlebar overflow boundary cannot clip it.
• Delegate collision handling, outside-click dismissal, Escape handling, and focus restoration to the shared primitive.
• Keep the panel responsive to narrow and short windows without relaxing titlebar layout constraints.

Verification

• corepack pnpm run ts-check
• corepack pnpm run lint
• corepack pnpm run format
• corepack pnpm test — 285 files, 2,139 tests
• corepack pnpm run build
• Runtime/UI verification completed or not applicable — manual visual check requested

Safety and Compatibility

• Local BYOK and signed-in OOMOL modes were considered separately; this renderer-only positioning change does not alter either flow.
• No credential was exposed to the renderer, logs, fixtures, screenshots, or committed files.
• Agent tools, permissions, and system prompts remain aligned; they are unaffected.
• Migration, packaging, endpoint, and update implications were considered; none are introduced.
• Relevant documentation and tests were updated or are not applicable; the existing full suite passes.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: f8fb82aa-8cb4-4c89-8b22-6ac786ff073c

📥 Commits

Reviewing files that changed from the base of the PR and between a0194e1 and 111c715.

📒 Files selected for processing (1)

• src/components/app-shell/BillingUsagePopover.tsx

---

Summary by CodeRabbit

• Bug Fixes
  • Improved the billing usage popover’s opening, closing, and focus behavior.
  • Added a built-in close control for more consistent interaction.
  • Preserved billing usage details, error handling, and navigation functionality.

Walkthrough

BillingUsagePopover now uses Radix UI Popover primitives with controlled open state and onOpenChange handling. The billing usage button is rendered through PopoverTrigger, while the existing usage content is placed inside PopoverContent. The header close button uses PopoverClose. Custom refs, pointer and keyboard handlers, and focus restoration logic were removed. Billing data handling and details navigation remain unchanged.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title follows the required type(scope): subject format and accurately describes the billing usage popover portal change.
Description check	✅ Passed	The description matches the template with Summary, Verification, and Safety and Compatibility sections filled out.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch fix/billing-usage-popover-portal

---

_{Comment @coderabbitai help to get the list of available commands.}