feat(pagespeed): add API client, SWR hooks, and sidebar navigation

- PageSpeed API client with types for config, checks, and audits
- SWR hooks: usePageSpeedConfig, usePageSpeedLatest, usePageSpeedHistory
- GaugeIcon added to sidebar under Infrastructure group

lib/api/pagespeed.ts

@@ -0,0 +1,83 @@
+import apiRequest from './client'
+
+// * Types for PageSpeed Insights monitoring
+
+export interface PageSpeedConfig {
+  site_id: string
+  enabled: boolean
+  frequency: 'daily' | 'weekly' | 'monthly'
+  url: string | null
+  next_check_at: string | null
+  created_at: string
+  updated_at: string
+}
+
+export interface AuditSummary {
+  id: string
+  title: string
+  description: string
+  score: number | null
+  display_value?: string
+  savings_ms?: number
+  category: 'opportunity' | 'diagnostic' | 'passed'
+}
+
+export interface PageSpeedCheck {
+  id: string
+  site_id: string
+  strategy: 'mobile' | 'desktop'
+  performance_score: number | null
+  accessibility_score: number | null
+  best_practices_score: number | null
+  seo_score: number | null
+  lcp_ms: number | null
+  cls: number | null
+  tbt_ms: number | null
+  fcp_ms: number | null
+  si_ms: number | null
+  tti_ms: number | null
+  audits: AuditSummary[] | null
+  triggered_by: 'scheduled' | 'manual'
+  checked_at: string
+}
+
+export async function getPageSpeedConfig(siteId: string): Promise<PageSpeedConfig> {
+  return apiRequest<PageSpeedConfig>(`/sites/${siteId}/pagespeed/config`)
+}
+
+export async function updatePageSpeedConfig(
+  siteId: string,
+  config: { enabled: boolean; frequency: string; url?: string }
+): Promise<PageSpeedConfig> {
+  return apiRequest<PageSpeedConfig>(`/sites/${siteId}/pagespeed/config`, {
+    method: 'PUT',
+    body: JSON.stringify(config),
+  })
+}
+
+export async function getPageSpeedLatest(siteId: string): Promise<PageSpeedCheck[]> {
+  const res = await apiRequest<{ checks: PageSpeedCheck[] }>(`/sites/${siteId}/pagespeed/latest`)
+  return res?.checks ?? []
+}
+
+export async function getPageSpeedHistory(
+  siteId: string,
+  strategy: 'mobile' | 'desktop' = 'mobile',
+  days = 90
+): Promise<PageSpeedCheck[]> {
+  const res = await apiRequest<{ checks: PageSpeedCheck[] }>(
+    `/sites/${siteId}/pagespeed/history?strategy=${strategy}&days=${days}`
+  )
+  return res?.checks ?? []
+}
+
+export async function getPageSpeedCheck(siteId: string, checkId: string): Promise<PageSpeedCheck> {
+  return apiRequest<PageSpeedCheck>(`/sites/${siteId}/pagespeed/checks/${checkId}`)
+}
+
+export async function triggerPageSpeedCheck(siteId: string): Promise<PageSpeedCheck[]> {
+  const res = await apiRequest<{ checks: PageSpeedCheck[] }>(`/sites/${siteId}/pagespeed/check`, {
+    method: 'POST',
+  })
+  return res?.checks ?? []
+}