improve timezone discovery

frontend/src/components/ParticipantManager.tsx

@@ -6,7 +6,6 @@ import { Label } from '@/components/ui/label';
 import { UserPlus, Trash2, User, Pencil, Check, X, AlertCircle } from 'lucide-react';
 import { useToast } from '@/hooks/use-toast';
 import { getAvatarColor } from '@/lib/utils';
-import { TimezoneSelector } from '@/components/TimezoneSelector';
 
 interface ParticipantManagerProps {
   participants: Participant[];
@@ -23,12 +22,10 @@ export const ParticipantManager = ({
 }: ParticipantManagerProps) => {
   const [name, setName] = useState('');
   const [email, setEmail] = useState('');
-  const [timezone, setTimezone] = useState('America/Toronto');
   const [icsLink, setIcsLink] = useState('');
 
   // Edit state
   const [editingId, setEditingId] = useState<string | null>(null);
-  const [editTimezone, setEditTimezone] = useState('');
   const [editIcsLink, setEditIcsLink] = useState('');
   const [isUpdating, setIsUpdating] = useState(false);
 
@@ -49,7 +46,7 @@ export const ParticipantManager = ({
     onAddParticipant({
       name: name.trim(),
       email: email.trim(),
-      timezone: timezone.trim() || 'America/Toronto',
+      timezone: 'America/Toronto',
       icsLink: icsLink.trim() || ''
     });
     setName('');
@@ -64,13 +61,11 @@ export const ParticipantManager = ({
 
   const startEditing = (participant: Participant) => {
     setEditingId(participant.id);
-    setEditTimezone(participant.timezone);
     setEditIcsLink(participant.icsLink || '');
   };
 
   const cancelEditing = () => {
     setEditingId(null);
-    setEditTimezone('');
     setEditIcsLink('');
   };
 
@@ -80,7 +75,6 @@ export const ParticipantManager = ({
     setIsUpdating(true);
     try {
       await onUpdateParticipant(participantId, {
-        timezone: editTimezone,
         ics_url: editIcsLink || undefined,
       });
       toast({
@@ -118,7 +112,7 @@ export const ParticipantManager = ({
         </h3>
 
         <form onSubmit={handleSubmit} className="space-y-4">
-          <div className="grid gap-4 sm:grid-cols-2 lg:grid-cols-4">
+          <div className="grid gap-4 sm:grid-cols-2 lg:grid-cols-3">
             <div className="space-y-2">
               <Label htmlFor="name">Name</Label>
               <Input
@@ -142,14 +136,6 @@ export const ParticipantManager = ({
               />
             </div>
 
-            <div className="space-y-2">
-              <Label>Timezone</Label>
-              <TimezoneSelector
-                value={timezone}
-                onChange={setTimezone}
-              />
-            </div>
-
             <div className="space-y-2">
               <Label htmlFor="icsLink">Calendar ICS Link</Label>
               <Input
@@ -203,24 +189,15 @@ export const ParticipantManager = ({
                       </div>
                     </div>
 
-                    <div className="grid gap-4 sm:grid-cols-2">
-                      <div className="space-y-2">
-                        <Label>Timezone</Label>
-                        <TimezoneSelector
-                          value={editTimezone}
-                          onChange={setEditTimezone}
-                        />
-                      </div>
-                      <div className="space-y-2">
-                        <Label htmlFor={`edit-ics-${participant.id}`}>Calendar ICS Link</Label>
-                        <Input
-                          id={`edit-ics-${participant.id}`}
-                          value={editIcsLink}
-                          onChange={(e) => setEditIcsLink(e.target.value)}
-                          placeholder="https://..."
-                          className="bg-card"
-                        />
-                      </div>
+                    <div className="space-y-2">
+                      <Label htmlFor={`edit-ics-${participant.id}`}>Calendar ICS Link</Label>
+                      <Input
+                        id={`edit-ics-${participant.id}`}
+                        value={editIcsLink}
+                        onChange={(e) => setEditIcsLink(e.target.value)}
+                        placeholder="https://..."
+                        className="bg-card"
+                      />
                     </div>
 
                     <div className="flex gap-2">
@@ -258,8 +235,6 @@ export const ParticipantManager = ({
                         <div className="text-sm text-muted-foreground flex flex-wrap gap-x-2">
                           <span>{participant.email}</span>
                           <span className="text-muted-foreground/60">•</span>
-                          <span>{participant.timezone}</span>
-                          <span className="text-muted-foreground/60">•</span>
                           {participant.icsLink ? (
                             <span className="text-primary truncate max-w-[200px]" title={participant.icsLink}>
                               ICS linked