feat(pages): add Wiki / Pages feature

[Rishavraaj]

Summary

Adds a Wiki / Pages feature to Zuko — a rich-text knowledge base where teams can write and organize findings, decisions, and runbooks. Pages are scoped to an organization, support nested subpages, and use Editor.js as the editor with autosave.

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Changes

Database

• New page table: stores title, blocks (Editor.js JSON), version, parentId (for nesting), and org/user relations
• Migration: 20260713082325_add_pages_and_page_attachments

Backend (apps/backend)

• pages.module.ts — registers the pages feature module; imported into app.module.ts
• pages.controller.ts — REST endpoints: GET /pages, GET /pages/:id, POST /pages, PATCH /pages/:id, DELETE /pages/:id; guarded by AuthGuard + OrganizationGuard
• pages.service.ts — business logic: create, read, update, delete with parent-cycle guard (prevents a page being nested under its own child)
• pages.repository.ts — Prisma queries; all scoped to the caller's organization
• dto/page.dto.ts — Zod schemas for create/update request validation

Frontend (apps/web)

• /pages — list view using the shared BaseTable pattern (same as contacts/companies/tasks); title cell shows hover-reveal icons to open in drawer or full page
• /pages/[id] — full-page editor: two-column layout with Editor.js on the left and a metadata sidebar (last updated, table of contents, subpages) on the right; read/edit toggle switch; autosave with "Saving…" / "Saved ✓" indicator
• PageDrawer — slide-over drawer that opens when clicking a page from the list; shows the page editor inline without leaving the list
• use-page-detail-editor.ts — shared hook used by both PageDetail and PageDrawer for save state and cache sync
• PageTableOfContents — parses Editor.js heading blocks and renders an on-page anchor list
• lib/api/pages.ts — typed API client for all pages endpoints
• query-options.ts — TanStack Query options for pages list and page detail (staleTime: Infinity on detail to avoid remounting the editor on navigation)
• application-layout.tsx — added "Wiki" nav item

UI Kit (libs/ui-kit)

• WikiEditor — Editor.js wrapper (dynamic import, SSR-disabled); tools: header, list (with checklist), code, quote, table, inline code, marker, embed, delimiter, warning
• WikiPage — autosave layer on top of WikiEditor; debounces saves by 2 s, fires onSaveStart / onSaveComplete / onSaveError callbacks
• Drawer — Headless UI slide-over component
• globals.css — Editor.js typography overrides: font sizes, line heights, checklist checkbox colors/alignment, inline code styles, dark mode text colors
• panel-right.svg — Lucide panel-right icon in public/icons for the drawer-open button

Models (libs/models)

• editor-markdown.ts — utility to convert Editor.js blocks to plain Markdown (for MCP/search use later)

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Test Plan

• GET /pages returns empty list for a fresh org
• Create page via "New Page" — opens in drawer, title defaults to "Untitled"
• Edit title in drawer and full-page view — saves on blur, updates list
• Write content in editor — autosaves after 2 s; "Saving…" then "Saved ✓" appears
• Navigate away and back — content persists without a network refetch
• Create a subpage from the sidebar — appears under parent in the subpages list
• Delete a page — subpages are also removed; drawer closes if deleted page was open
• Cross-org isolation — page from org A is not visible or editable from org B
• Dark mode — text, checkboxes, and inline code all render correctly