Codebase audit: remove dead code, fix broken patterns, consolidate duplicates; v2.0.27

- Remove unused prop-types dep, deprecated useOutboundLinkTracking export
- Fix missing linkClicks key in analyticsEvents initial state (B-01)
- Export ADMIN_SESSION_COOKIE from auth.js; remove local copy in admin-auth.js (D-02)
- Remove cookieFlags() wrapper in auth.js and study-helpers.js; use cookieSecureFlag() directly (U-04)
- Remove ADMIN_SESSION_TTL_MS duplicate from config.js (D-01)
- Remove DEFAULT_SEO/DEFAULT_LEGAL/DEFAULT_REDIRECT_RULES/DEFAULT_PODCAST_FEATURED_LINKS/DEFAULT_PUBLISH_STATE
  duplicates from config.js; re-export from helpers.js (D-04, fixes sitemapPaths divergence)
- Fix email.js hardcoded fallback strings to use DEFAULT_RESEND_TO/DEFAULT_RESEND_REPLY_TO (M-02)
- Remove duplicate normalizeIp, isPrivateOrLocalIp, normalizeRedirectPath, sanitizeUrl,
  sanitizeRedirectRules bodies from study-helpers.js; re-export from helpers.js (D-03)
- Fix pruneStatsByDays to import VISITOR_RETENTION_DAYS_DEFAULT from config.js (B-02)
- Fix createTitusDownloadToken to use DOWNLOAD_TOKEN_TTL_MS constant (B-03)
- Remove normalizeMessageType duplicate from study-helpers.js (U-03/D-08)
- Remove dead wantsWelcome variable in contact.js; use shouldSendWelcome (B-04)
- Replace dynamic imports in contact.js with static imports (B-07)
- Remove dead wantsWelcome=true in study-auth.js (B-05)
- Merge duplicate import blocks in analytics.js and public.js (D-05, D-06)
- Replace dynamic readFile re-import in nuggets-host-upload.js (B-06)
- Replace hardcoded SITE_URL fallbacks with getCanonicalBaseUrl() (M-06)
- Replace raw resend.emails.send in study-account.js with sendResendEmailWithRetry (M-01)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/routes/contact.js

@@ -1,12 +1,13 @@
 import { randomUUID } from 'node:crypto'
 import { Resend } from 'resend'
 import { requireAdminAuth } from '../auth.js'
-import { escapeHtml, splitName } from '../helpers.js'
+import { escapeHtml, splitName, buildAbsoluteUrl } from '../helpers.js'
 import {
   MAX_CONTACT_SUBMISSIONS,
   MAX_QUESTIONS,
   USE_RESEND_AUTOMATION_WELCOME,
   DEFAULT_SEO,
+  DATA_FILE,
 } from '../config.js'
 import { state } from '../state.js'
 import {
@@ -16,6 +17,7 @@ import {
   normalizeContactEmailStatus,
   normalizeMessageType,
   fireWebhooks,
+  loadSiteContentFile,
 } from '../data.js'
 import {
   noteContactEmailCooldown,
@@ -130,7 +132,6 @@ export function register(app) {
       const submittedAt = new Date().toLocaleString('en-US', { dateStyle: 'medium', timeStyle: 'short' })
       const shouldSendWelcome = shouldSendWelcomeEmail({ subscribe })
 
-      const wantsWelcome = subscribe === true
       const submission = {
         id: randomUUID(),
         submittedAt: new Date().toISOString(),
@@ -138,9 +139,9 @@ export function register(app) {
         email: trimmedEmail,
         message: trimmedMessage,
         messageType: normalizedMessageType,
-        subscribe: wantsWelcome,
+        subscribe: shouldSendWelcome,
         archived: false,
-        emailStatus: normalizeContactEmailStatus(null, wantsWelcome),
+        emailStatus: normalizeContactEmailStatus(null, shouldSendWelcome),
       }
       state.contactSubmissions.unshift(submission)
       state.contactSubmissions = state.contactSubmissions.slice(0, MAX_CONTACT_SUBMISSIONS)
@@ -187,8 +188,6 @@ export function register(app) {
         let publishedSiteContent = state.cachedSiteContent
         if (!publishedSiteContent) {
           try {
-            const { loadSiteContentFile } = await import('../data.js')
-            const { DATA_FILE } = await import('../config.js')
             const published = await loadSiteContentFile(DATA_FILE)
             publishedSiteContent = published?.siteContent ?? null
           } catch { publishedSiteContent = null }
@@ -200,7 +199,6 @@ export function register(app) {
           : DEFAULT_SEO.canonicalUrl
         const welcomeSubject = process.env.RESEND_WELCOME_SUBJECT ?? emailConfig.welcomeEmailSubject ?? 'Welcome to Verse by Verse with Nate'
         const welcomeGreetingPrefix = emailConfig.welcomeEmailGreetingPrefix?.trim() || "Glad you're here"
-        const { buildAbsoluteUrl } = await import('../helpers.js')
         const welcomeTemplate = buildContactWelcomeEmailTemplate({
           greetingName,
           welcomeGreetingPrefix,