feat(audit-cleanup): finish all 15 outstanding items from verified backlog

Audit cleanup completion plan, all tiers shipped:

Tier 1 (security + data integrity)
- A.7 RTBF true wipe: redact email_messages body/subject/addresses for
  threads owned by deleted client; redact document_sends.recipient_email;
  collect file storage keys + delete blobs post-commit.
- A.8 user_permission_overrides FK: documented inline why cascade is
  correct (not set-null as audit suggested) — overrides have no value
  without their user.
- W2.14 PII redaction: camelCase normalization in audit.ts +
  error-events.service.ts isSensitiveKey; added city/postal/country/
  birth fragments. firstName/lastName/dateOfBirth/postalCode etc. now
  caught in BOTH masker paths. 12 new test cases lock the coverage.

Tier 2 (Documenso completion + refactor)
- C.2: documentEvents.recipient_email column + partial unique index for
  per-recipient webhook dedup (migration 0075). handleDocumentSigned
  now sets recipient_email on insert.
- Phase 2: completion_cc_emails distribution. handleDocumentCompleted
  reads documents.completionCcEmails, filters out signer-duplicates
  case-insensitively, fans signed PDF out to non-signer recipients.
- C.4: extracted createPublicInterest() service from the 346-line
  api/public/interests route. Route becomes a thin shell (rate-limit,
  port resolution, audit log, email fan-out). The trio creation logic
  is now unit-testable without an HTTP fixture.
- Phase 4: POST /api/v1/document-templates/[id]/detect-fields wired
  to document-field-detector.detectFields(). Sparkles "Auto-detect"
  button added to template-editor.tsx — maps DetectedField → marker
  with best-guess merge token (DATE / NAME / EMAIL); user retags.

Tier 3 (reporting + recommender snapshot lockfiles)
- W7.reports: extracted rollupStageRevenue / rollupStageCounts /
  computeTotalForecast / computeOccupancyRate / rollupBerthStatusCounts
  into src/lib/services/report-math.ts (pure functions). 16 new tests
  including an inline-snapshot lockfile on a representative 7-stage
  forecast. report-generators.ts now delegates.
- W7.recommender: 18 new toMatchSnapshot tripwires on classifyTier
  boundaries + computeHeat at canonical input points.

Tier 4 (rolling)
- W6.attach: fixed outdated CLAUDE.md claim — threshold banner is
  informational and never depended on IMAP; bounce monitoring (the
  IMAP poller) is separate.
- D.1 + D.2: documented deferral inline with full why-not-build-it
  reasoning so a future engineer sees the rationale.
- G.1: representative formatDate sweep (audit-log-list, user-list,
  document-templates merge tokens, document-signing email). Rest of
  the ~100 sites stay rolling.

Quality gates: 1420/1420 vitest (46 new tests above baseline of 1374),
tsc clean, 0 lint errors.

Plan: docs/superpowers/plans/2026-05-18-audit-cleanup-completion.md
Migration: 0075_c2_document_events_recipient_email.sql (applied to dev DB).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lib/audit.ts

@@ -109,9 +109,10 @@ export interface AuditLogParams {
 }
 
 // Lower-cased key fragments. A metadata key is masked if any fragment is
-// contained as a substring after lowercase + snake/kebab normalization.
-// Substring match catches `recipientEmail`, `sent_to_email`, `userEmail`,
-// `attempted_email`, `from_address`, `phone_number`, `passwordHash`, etc.
+// contained as a substring after camelCase→snake + lowercase + kebab→snake
+// normalization. Substring match catches `recipientEmail`, `sent_to_email`,
+// `userEmail`, `from_address`, `phone_number`, `passwordHash`, `firstName`,
+// `postalCode`, `dateOfBirth`, etc.
 const SENSITIVE_KEY_FRAGMENTS = [
   'email',
   'phone',
@@ -125,9 +126,12 @@ const SENSITIVE_KEY_FRAGMENTS = [
   'authorization',
   'cookie',
   'address', // physical/mailing addresses
+  'city',
+  'postal',
+  'country',
   'dob',
   'date_of_birth',
-  'birthdate',
+  'birth',
   'tax_id',
   'taxid',
   'national_id',
@@ -136,7 +140,7 @@ const SENSITIVE_KEY_FRAGMENTS = [
   'iban',
   'card_number',
   'cvv',
-  'recipient', // e.g. recipientEmail catches the parent too — preserves intent
+  'recipient',
   'first_name',
   'last_name',
   'full_name',
@@ -144,7 +148,10 @@ const SENSITIVE_KEY_FRAGMENTS = [
 ];
 
 function isSensitiveKey(key: string): boolean {
-  const k = key.toLowerCase().replace(/[-]/g, '_');
+  const k = key
+    .replace(/([a-z0-9])([A-Z])/g, '$1_$2')
+    .toLowerCase()
+    .replace(/[-]/g, '_');
   return SENSITIVE_KEY_FRAGMENTS.some((frag) => k.includes(frag));
 }