perf: reduce first-load JS bundle size below 200 kB budget

[sw-factory-automations]

Description

All 12 pages exceed the 200 kB first-load JS budget (gzip). The shared base alone is 252 kB across 19 chunks. Week-over-week increases of 17–87 kB on several pages (W19→W20) indicate growing bundle bloat. This affects initial page load time, especially on slower connections.

Source: metrics/weekly/2026-W20-perf.md

Acceptance Criteria

• Audit shared JS chunks to identify the largest contributors (Lexical, Supabase, Sentry, React, etc.)
• Apply next/dynamic with ssr: false to heavy client-only components not yet lazy-loaded (e.g., emoji picker, date picker, any remaining Lexical plugins loaded outside the editor page)
• Verify Sentry SDK is not statically imported in any client component (only via lazyCaptureException or instrumentation-client.ts)
• Verify lucide-react icons use named imports (tree-shakeable) rather than barrel imports
• At least 3 pages drop below 200 kB first-load JS (gzip), or the shared base drops below 200 kB
• pnpm lint && pnpm typecheck && pnpm test pass
• No visual or functional regressions in E2E tests

Dependencies

None

Technical Notes

• Current dynamic imports: src/components/page-content-client.tsx, workspace-home-client.tsx, page-icon.tsx, landing-demo-editor.tsx, settings-page-content.tsx, danger-zone-settings.tsx, lazy-route-error.tsx, workspace-settings-form.tsx, page-view-client.tsx, settings-page-client.tsx
• Sentry already uses lazy capture (src/lib/capture.ts) — verify no other files import @sentry/nextjs directly in client code
• @lexical/* packages (12 packages) are the heaviest dependency group — ensure they only load on the editor page, not in shared chunks
• Use npx @next/bundle-analyzer or Turbopack build output to identify chunk composition
• Reference .agents/conventions.md for dynamic import patterns

Approval Required

This is a HIGH risk change:

• Modifying import structure across many files risks breaking code-splitting boundaries
• Dynamic imports change component loading behavior (loading states, hydration timing)
• Lexical editor chunk restructuring could affect editor initialization
• Requires careful verification that no functionality regresses

Comment "approved" to release this to the automation queue.

[sw-factory-automations]

Approval Required

This is a HIGH risk change:

• Modifying import structure across many files risks breaking code-splitting boundaries
• Dynamic imports change component loading behavior (loading states, hydration timing)
• Lexical editor chunk restructuring could affect editor initialization
• Requires careful verification that no functionality regresses

Comment "approved" to release this to the automation queue.