feat: implement PostHog event tracking plan

Add trackEvent() calls for all user actions in the tracking plan:
- Vault: vault_opened (with has_git, note_count), vault_switched
- Notes: note_created (with has_type, creation_path), note_deleted,
  note_trashed, note_archived, note_favorited, note_unfavorited
- Git: commit_made, sync_triggered
- Search: search_used
- Editor: raw_mode_toggled, wikilink_inserted
- Types & Views: type_created, view_created
- Telemetry: telemetry_opted_in, telemetry_opted_out

All events gated by PostHog initialization (only fires when opted in).
No PII in any event properties — counts, booleans, and enums only.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/hooks/useAppKeyboard.ts

@@ -1,5 +1,6 @@
 import { useEffect } from 'react'
 import type { ViewMode } from './useViewMode'
+import { trackEvent } from '../lib/telemetry'
 
 interface KeyboardActions {
   onQuickOpen: () => void
@@ -104,6 +105,7 @@ export function useAppKeyboard({
       // Cmd+Shift+F: full-text search (distinct from Cmd+F browser find)
       if ((e.metaKey || e.ctrlKey) && e.shiftKey && e.key === 'f') {
         e.preventDefault()
+        trackEvent('search_used')
         onSearch()
         return
       }

src/hooks/useAutoSync.ts

@@ -2,6 +2,7 @@ import { useCallback, useEffect, useRef, useState } from 'react'
 import { invoke } from '@tauri-apps/api/core'
 import { isTauri, mockInvoke } from '../mock-tauri'
 import type { GitPullResult, GitPushResult, GitRemoteStatus, LastCommitInfo, SyncStatus } from '../types'
+import { trackEvent } from '../lib/telemetry'
 
 const DEFAULT_INTERVAL_MS = 5 * 60_000
 
@@ -219,5 +220,10 @@ export function useAutoSync({
   const pausePull = useCallback(() => { pauseRef.current = true }, [])
   const resumePull = useCallback(() => { pauseRef.current = false }, [])
 
-  return { syncStatus, lastSyncTime, conflictFiles, lastCommitInfo, remoteStatus, triggerSync: performPull, pullAndPush, pausePull, resumePull, handlePushRejected }
+  const triggerSync = useCallback(() => {
+    trackEvent('sync_triggered')
+    performPull()
+  }, [performPull])
+
+  return { syncStatus, lastSyncTime, conflictFiles, lastCommitInfo, remoteStatus, triggerSync, pullAndPush, pausePull, resumePull, handlePushRejected }
 }

src/hooks/useCommitFlow.ts

@@ -1,5 +1,6 @@
 import { useCallback, useState } from 'react'
 import type { GitPushResult } from '../types'
+import { trackEvent } from '../lib/telemetry'
 
 interface CommitFlowConfig {
   savePending: () => Promise<void | boolean>
@@ -25,6 +26,7 @@ export function useCommitFlow({ savePending, loadModifiedFiles, commitAndPush, s
       await savePending()
       const result = await commitAndPush(message)
       if (result.status === 'ok') {
+        trackEvent('commit_made')
         setToastMessage('Committed and pushed')
       } else if (result.status === 'rejected') {
         setToastMessage('Committed, but push rejected — remote has new commits. Pull first.')

src/hooks/useDeleteActions.ts

@@ -2,6 +2,7 @@ import { useCallback, useMemo, useState } from 'react'
 import { invoke } from '@tauri-apps/api/core'
 import { isTauri, mockInvoke } from '../mock-tauri'
 import type { VaultEntry } from '../types'
+import { trackEvent } from '../lib/telemetry'
 
 interface ConfirmDeleteState {
   title: string
@@ -50,7 +51,10 @@ export function useDeleteActions({
       onConfirm: async () => {
         setConfirmDelete(null)
         const ok = await deleteNoteFromDisk(path)
-        if (ok) setToastMessage('Note permanently deleted')
+        if (ok) {
+          trackEvent('note_deleted')
+          setToastMessage('Note permanently deleted')
+        }
       },
     })
   }, [deleteNoteFromDisk, setToastMessage])

src/hooks/useEntryActions.ts

@@ -1,6 +1,7 @@
 import { useCallback } from 'react'
 import type { VaultEntry } from '../types'
 import type { FrontmatterOpOptions } from './frontmatterOps'
+import { trackEvent } from '../lib/telemetry'
 
 interface EntryActionsConfig {
   entries: VaultEntry[]
@@ -32,6 +33,7 @@ export function useEntryActions({
     // Optimistic: update UI immediately, write to disk async with rollback on failure
     const trashedAt = Date.now() / 1000
     updateEntry(path, { trashed: true, trashedAt })
+    trackEvent('note_trashed')
     setToastMessage('Note moved to trash')
     const now = new Date().toISOString().slice(0, 10)
     try {
@@ -64,6 +66,7 @@ export function useEntryActions({
     await onBeforeAction?.(path)
     // Optimistic: update UI immediately, write to disk async with rollback on failure
     updateEntry(path, { archived: true })
+    trackEvent('note_archived')
     setToastMessage('Note archived')
     try {
       await handleUpdateFrontmatter(path, '_archived', true, { silent: true })
@@ -129,6 +132,7 @@ export function useEntryActions({
     const entry = entries.find((e) => e.path === path)
     if (!entry) return
     if (entry.favorite) {
+      trackEvent('note_unfavorited')
       updateEntry(path, { favorite: false, favoriteIndex: null })
       try {
         await handleDeleteProperty(path, '_favorite', { silent: true })
@@ -139,6 +143,7 @@ export function useEntryActions({
         setToastMessage('Failed to unfavorite — rolled back')
       }
     } else {
+      trackEvent('note_favorited')
       const maxIndex = entries.filter((e) => e.favorite).reduce((max, e) => Math.max(max, e.favoriteIndex ?? 0), 0)
       const newIndex = maxIndex + 1
       updateEntry(path, { favorite: true, favoriteIndex: newIndex })

src/hooks/useNoteCreation.ts

@@ -3,6 +3,7 @@ import { invoke } from '@tauri-apps/api/core'
 import { isTauri, addMockEntry } from '../mock-tauri'
 import type { VaultEntry } from '../types'
 import { resolveEntry } from '../utils/wikilink'
+import { trackEvent } from '../lib/telemetry'
 
 export interface NewEntryParams {
   path: string
@@ -250,6 +251,7 @@ export function useNoteCreation(config: NoteCreationConfig, tabDeps: CreationTab
   const handleCreateNote = useCallback((title: string, type: string) => {
     const template = resolveTemplate(entries, type)
     persistNew(resolveNewNote(title, type, config.vaultPath, template))
+    trackEvent('note_created', { has_type: type !== 'Note' ? 1 : 0, creation_path: 'plus_button' })
   }, [entries, persistNew, config.vaultPath])
 
   const handleCreateNoteImmediate = useCallback((type?: string) => {
@@ -257,6 +259,7 @@ export function useNoteCreation(config: NoteCreationConfig, tabDeps: CreationTab
       entries, vaultPath: config.vaultPath, pendingNames: pendingNamesRef.current,
       openTabWithContent, addEntry, trackUnsaved: config.trackUnsaved, markContentPending: config.markContentPending,
     }, type)
+    trackEvent('note_created', { has_type: type ? 1 : 0, creation_path: type ? 'type_section' : 'cmd_n' })
   }, [entries, openTabWithContent, addEntry, config.vaultPath, config.trackUnsaved, config.markContentPending])
 
   const handleCreateNoteForRelationship = useCallback((title: string): Promise<boolean> => {
@@ -269,7 +272,10 @@ export function useNoteCreation(config: NoteCreationConfig, tabDeps: CreationTab
 
   const handleOpenDailyNote = useCallback(() => openDailyNote(entries, handleSelectNote, persistNew, config.vaultPath), [entries, handleSelectNote, persistNew, config.vaultPath])
 
-  const handleCreateType = useCallback((typeName: string) => persistNew(resolveNewType(typeName, config.vaultPath)), [persistNew, config.vaultPath])
+  const handleCreateType = useCallback((typeName: string) => {
+    persistNew(resolveNewType(typeName, config.vaultPath))
+    trackEvent('type_created')
+  }, [persistNew, config.vaultPath])
 
   /** Create a Type entry file silently (no tab opened). Adds to state and persists to disk. */
   const createTypeEntrySilent = useCallback(async (typeName: string): Promise<VaultEntry> => {

src/hooks/useRawMode.ts

@@ -1,5 +1,6 @@
 import { useState, useCallback, useEffect } from 'react'
 import { getVaultConfig, updateVaultConfigField, subscribeVaultConfig } from '../utils/vaultConfigStore'
+import { trackEvent } from '../lib/telemetry'
 
 interface UseRawModeParams {
   activeTabPath: string | null
@@ -32,6 +33,7 @@ export function useRawMode({ activeTabPath, onFlushPending, onBeforeRawEnd }: Us
   const rawMode = rawEnabled && activeTabPath !== null
 
   const handleToggleRaw = useCallback(async () => {
+    trackEvent('raw_mode_toggled')
     if (rawEnabled) {
       onBeforeRawEnd?.()
       setRawEnabled(false)

src/hooks/useVaultSwitcher.ts

@@ -4,6 +4,7 @@ import { isTauri, mockInvoke } from '../mock-tauri'
 import { pickFolder } from '../utils/vault-dialog'
 import { loadVaultList, saveVaultList } from '../utils/vaultListStore'
 import type { VaultOption } from '../components/StatusBar'
+import { trackEvent } from '../lib/telemetry'
 
 export type { PersistedVaultList } from '../utils/vaultListStore'
 
@@ -91,6 +92,7 @@ export function useVaultSwitcher({ onSwitch, onToast }: UseVaultSwitcherOptions)
   }, [])
 
   const switchVault = useCallback((path: string) => {
+    trackEvent('vault_switched')
     setVaultPath(path)
     onSwitchRef.current()
   }, [])