wrap chain source, rescan and wallet-rename fields in real forms

three input sites lived in a div instead of a form, so pressing enter did
nothing and the button was the only way in. chain source url, rescan search
depth, and the inline wallet-rename field all get a <form onSubmit>, with
every non-submit button in each marked type="button" (the rescan card's
reset button was previously untyped, which would have submitted the form
once wrapped).

CoinsView.tsx has no text inputs (checkbox + buttons only) and
SeedPhraseInput.tsx deliberately hijacks enter to advance between word boxes
rather than submit, so both are left alone.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

web/WalletSettingsView.tsx

@@ -206,7 +206,8 @@ const WalletNameField = ({ wallet, onSave, isPending }: WalletNameFieldProps) =>
   const trimmed = draft.trim();
   const dirty = trimmed !== wallet.name;
 
-  const commit = async () => {
+  const commit = async (ev?: React.FormEvent) => {
+    ev?.preventDefault();
     if (!trimmed || !dirty) {
       setDraft(wallet.name);
       setEditing(false);
@@ -242,7 +243,7 @@ const WalletNameField = ({ wallet, onSave, isPending }: WalletNameFieldProps) =>
   }
 
   return (
-    <div className="flex min-w-0 items-center gap-1.5">
+    <form onSubmit={commit} className="flex min-w-0 items-center gap-1.5">
       <Input
         ref={inputRef}
         autoFocus
@@ -251,7 +252,6 @@ const WalletNameField = ({ wallet, onSave, isPending }: WalletNameFieldProps) =>
         disabled={isPending}
         onChange={(ev) => setDraft(ev.target.value)}
         onKeyDown={(ev) => {
-          if (ev.key === 'Enter') void commit();
           if (ev.key === 'Escape') cancel();
         }}
         className="h-7 max-w-56 text-sm font-semibold"
@@ -259,13 +259,13 @@ const WalletNameField = ({ wallet, onSave, isPending }: WalletNameFieldProps) =>
         autoComplete="off"
         spellCheck={false}
       />
-      <Button size="icon" variant="ghost" className="h-7 w-7" onClick={commit} disabled={isPending || !trimmed}>
+      <Button type="submit" size="icon" variant="ghost" className="h-7 w-7" disabled={isPending || !trimmed}>
         <Check className="h-3.5 w-3.5" />
       </Button>
-      <Button size="icon" variant="ghost" className="h-7 w-7" onClick={cancel} disabled={isPending}>
+      <Button type="button" size="icon" variant="ghost" className="h-7 w-7" onClick={cancel} disabled={isPending}>
         <X className="h-3.5 w-3.5" />
       </Button>
-    </div>
+    </form>
   );
 };