feat(interests): Email / Call / WhatsApp deep-links on interest header

The interest detail is the rep's workbench — but until now, calling or
emailing the lead meant navigating away to the client page first. Surface
the same Email / Call / WhatsApp affordances that already live on the
client header right where the work is happening.

  - getInterestById: extended to also resolve the linked client's primary
    phone (display value + canonical E.164 form for wa.me).
    `clientPrimaryEmail` is the same column we surfaced earlier for the
    EOI prereq checklist; this commit just adds the phone columns
    alongside it.

  - InterestDetailHeader: new contact-actions row tucked under the meta
    line. Each button is asChild over a real <a href> so middle-click,
    Cmd-click, and screen-readers behave correctly. Renders only the
    buttons whose underlying contact channel is present (Email-only when
    no phone is on file, etc.). The whole row is hidden when the client
    has no contacts at all.

  - WhatsApp number prefers the E.164 form; falls back to digits-stripped
    display value when the canonical form is missing.

tsc clean. vitest 835/835 pass. ESLint clean on every file touched.

Closes audit recommendation #1 (top-of-list — biggest sales-workflow
win per click saved).

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

src/components/interests/interest-detail-header.tsx

@@ -2,9 +2,20 @@
 
 import { useState } from 'react';
 import { useMutation, useQueryClient } from '@tanstack/react-query';
-import { Pencil, Archive, RotateCcw, Trophy, XCircle, RefreshCcw } from 'lucide-react';
+import {
+  Pencil,
+  Archive,
+  RotateCcw,
+  Trophy,
+  XCircle,
+  RefreshCcw,
+  Mail,
+  MessageCircle,
+  Phone,
+} from 'lucide-react';
 import Link from 'next/link';
 
+import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
 import { TagBadge } from '@/components/shared/tag-badge';
 import { ArchiveConfirmDialog } from '@/components/shared/archive-confirm-dialog';
@@ -36,6 +47,12 @@ interface InterestDetailHeaderProps {
     id: string;
     clientId: string;
     clientName: string | null;
+    /** Primary contact channels resolved from the linked client. The header
+     *  uses these to render Email / Call / WhatsApp buttons so the rep
+     *  doesn't have to navigate to the client page just to reach out. */
+    clientPrimaryEmail?: string | null;
+    clientPrimaryPhone?: string | null;
+    clientPrimaryPhoneE164?: string | null;
     berthId: string | null;
     berthMooringNumber: string | null;
     pipelineStage: string;
@@ -71,6 +88,16 @@ export function InterestDetailHeader({ portSlug, interest }: InterestDetailHeade
   const outcomeBadge = interest.outcome ? OUTCOME_BADGE[interest.outcome] : null;
   const isClosed = !!interest.outcome;
 
+  // Contact deep-links — resolved from the linked client's primary channels.
+  // wa.me requires the digits-only E.164 number (no leading "+"); fall back to
+  // stripping non-digits from the display value when the canonical form is
+  // missing.
+  const whatsappNumber = interest.clientPrimaryPhoneE164
+    ? interest.clientPrimaryPhoneE164.replace(/^\+/, '')
+    : interest.clientPrimaryPhone
+      ? interest.clientPrimaryPhone.replace(/[^\d]/g, '')
+      : null;
+
   const reopenMutation = useMutation({
     mutationFn: () =>
       apiFetch(`/api/v1/interests/${interest.id}/outcome`, { method: 'DELETE', body: {} }),
@@ -200,6 +227,65 @@ export function InterestDetailHeader({ portSlug, interest }: InterestDetailHeade
                 ))}
               </div>
             )}
+
+            {/* Contact deep-links — let the rep email / call / WhatsApp the
+                client without leaving the interest workspace. Resolved from
+                the linked client's primary contact channels (server-side
+                fetch in getInterestById). */}
+            {interest.clientPrimaryEmail || interest.clientPrimaryPhone || whatsappNumber ? (
+              <div className="flex flex-wrap items-center gap-1.5 pt-1">
+                {interest.clientPrimaryEmail ? (
+                  <Button
+                    asChild
+                    variant="outline"
+                    size="sm"
+                    className="h-8 gap-1.5 px-2.5 [&_svg]:size-3.5"
+                  >
+                    <a
+                      href={`mailto:${interest.clientPrimaryEmail}`}
+                      aria-label={`Email ${interest.clientPrimaryEmail}`}
+                    >
+                      <Mail />
+                      Email
+                    </a>
+                  </Button>
+                ) : null}
+                {interest.clientPrimaryPhone ? (
+                  <Button
+                    asChild
+                    variant="outline"
+                    size="sm"
+                    className="h-8 gap-1.5 px-2.5 [&_svg]:size-3.5"
+                  >
+                    <a
+                      href={`tel:${interest.clientPrimaryPhone}`}
+                      aria-label={`Call ${interest.clientPrimaryPhone}`}
+                    >
+                      <Phone />
+                      Call
+                    </a>
+                  </Button>
+                ) : null}
+                {whatsappNumber ? (
+                  <Button
+                    asChild
+                    variant="outline"
+                    size="sm"
+                    className="h-8 gap-1.5 px-2.5 [&_svg]:size-3.5"
+                  >
+                    <a
+                      href={`https://wa.me/${whatsappNumber}`}
+                      target="_blank"
+                      rel="noopener noreferrer"
+                      aria-label={`Message on WhatsApp`}
+                    >
+                      <MessageCircle />
+                      WhatsApp
+                    </a>
+                  </Button>
+                ) : null}
+              </div>
+            ) : null}
           </div>
 
           {/* Top-right actions. Won/Lost are sales-critical and read as text

src/components/interests/interest-detail.tsx

@@ -16,6 +16,18 @@ interface InterestData {
   portId: string;
   clientId: string;
   clientName: string | null;
+  /** Linked client's primary email (display value). Powers the header
+   *  "Email" button and the EOI prereq checklist. */
+  clientPrimaryEmail: string | null;
+  /** Linked client's primary phone (display value). Powers the header
+   *  "Call" button. */
+  clientPrimaryPhone: string | null;
+  /** Linked client's primary phone in E.164 form ("+1XXXXXXXXXX"). Used
+   *  by wa.me to assemble the WhatsApp deep-link. */
+  clientPrimaryPhoneE164: string | null;
+  /** True when the linked client has any primary address row. Used by
+   *  the EOI prereq checklist on the Documents tab. */
+  clientHasAddress: boolean;
   berthId: string | null;
   berthMooringNumber: string | null;
   pipelineStage: string;
@@ -39,6 +51,8 @@ interface InterestData {
   archivedAt: string | null;
   createdAt: string;
   updatedAt: string;
+  outcome?: string | null;
+  outcomeReason?: string | null;
   tags: Array<{ id: string; name: string; color: string }>;
 }