feat: add sidebar config-driven, compact mode, and footer dropdown plan

[PlayerNguyen]

Summary

Adds the plan file for implementing a configurable, searchable sidebar with compact mode, nested sub-items, and a footer dropdown.

Related Issue

Refs: #15, #16, #17, #18

Type

• Feature
• Bug fix
• Refactor
• Infrastructure / CI
• Documentation
• Other: ___

Scope

• dashbore-api (apps/api/)
• dashbore-ui (apps/ui/)
• dashbore-common (packages/common/)
• dashbore-database (packages/database/)
• dashbore-business (packages/business/)
• dashbore-cache (packages/cache/)
• Root / config

Changes

• Added .opencode/plans/08-07-2026/17-28_sidebar-compact-mode-and-config.md

Motivation

Structured plan to guide the sidebar refactor into a config-driven, searchable, compact-mode-enabled component with footer dropdown.

Dependencies

None.

Testing

N/A — documentation only.

Checklist

• No console.log left in production code
• No secrets or keys committed
• Path aliases used correctly (@/, @common/)
• New code has tests (if applicable)
• API changes update OpenAPI spec (if applicable)
• UI changes work with Mantine + Tailwind v4 (if applicable)

Screenshots / Logs

N/A