feat(documents-wizard): replace UUID-paste fields with searchable pickers + inline upload

Reps no longer have to copy/paste UUIDs into the New-document wizard.

Three UUID inputs replaced:
- Template id Input → DocumentTemplatePicker (queries /api/v1/document-templates
  with name search; filters to isActive=true)
- Uploaded file id Input → inline FileUploadZone (drop or browse PDF; surfaces
  the uploaded file id directly to the wizard via the new onUploadComplete
  signature)
- Subject id Input → conditional picker: ClientPicker / CompanyPicker /
  YachtPicker / InterestPicker depending on the subject-type dropdown.
  Reservation falls back to Input for now (no ReservationPicker yet).

Other polish in the wizard:
- SIGNER_ROLES labels capitalized in the role select (client → Client, etc.)
  via a formatSignerRole() helper. Internal values stay lowercase.
- Pinned h-9 on Select triggers so the type/subject row + signer-role select
  vertically align with their adjacent inputs.
- Subject-type change now resets subjectId — picker options are type-specific
  and a stale id from a different entity table would be invalid.

Infrastructure for hub uploads (will be consumed in a follow-up dropdown +
drag-drop pass):
- /api/v1/files/upload route now parses folderId from FormData (schema
  already supported it).
- FileUploadZone accepts a folderId prop and forwards it, plus a new
  onUploadComplete(file) callback shape that surfaces { id, filename } on
  each successful upload. Existing per-entity callers (Files tab on clients,
  companies, yachts, interests) ignore the arg, no behaviour change.

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

src/components/interests/interest-picker.tsx

@@ -0,0 +1,115 @@
+'use client';
+
+import { useState } from 'react';
+import { Check, ChevronsUpDown } from 'lucide-react';
+import { useQuery } from '@tanstack/react-query';
+
+import { Button } from '@/components/ui/button';
+import {
+  Command,
+  CommandEmpty,
+  CommandGroup,
+  CommandInput,
+  CommandItem,
+  CommandList,
+} from '@/components/ui/command';
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
+import { useDebounce } from '@/hooks/use-debounce';
+import { apiFetch } from '@/lib/api/client';
+import { cn } from '@/lib/utils';
+
+interface InterestOption {
+  id: string;
+  clientId: string;
+  clientName?: string;
+  pipelineStage?: string;
+  // Some list endpoints surface the linked client inline; we display whatever's
+  // available with a fallback to a short id.
+}
+
+interface InterestPickerProps {
+  value: string | null;
+  onChange: (interestId: string | null) => void;
+  placeholder?: string;
+  disabled?: boolean;
+}
+
+export function InterestPicker({
+  value,
+  onChange,
+  placeholder = 'Select interest...',
+  disabled,
+}: InterestPickerProps) {
+  const [open, setOpen] = useState(false);
+  const [search, setSearch] = useState('');
+  const debounced = useDebounce(search, 300);
+
+  const { data } = useQuery<{ data: InterestOption[] }>({
+    queryKey: ['interest-picker', debounced],
+    queryFn: () =>
+      apiFetch(
+        `/api/v1/interests?search=${encodeURIComponent(debounced)}&page=1&limit=10&order=desc&includeArchived=false`,
+      ),
+    enabled: open,
+  });
+
+  const options = data?.data ?? [];
+
+  const selectedLabel = (() => {
+    if (!value) return placeholder;
+    const match = options.find((o) => o.id === value);
+    if (!match) return `Interest ${value.slice(0, 8)}`;
+    if (match.clientName) return `${match.clientName} — ${match.pipelineStage ?? 'open'}`;
+    return `Interest ${match.id.slice(0, 8)}`;
+  })();
+
+  return (
+    <Popover open={open} onOpenChange={setOpen}>
+      <PopoverTrigger asChild>
+        <Button
+          variant="outline"
+          role="combobox"
+          disabled={disabled}
+          className={cn('w-full justify-between', !value && 'text-muted-foreground')}
+        >
+          <span className="truncate">{selectedLabel}</span>
+          <ChevronsUpDown className="ml-2 h-4 w-4 shrink-0 opacity-50" />
+        </Button>
+      </PopoverTrigger>
+      <PopoverContent className="w-[320px] p-0" align="start">
+        <Command shouldFilter={false}>
+          <CommandInput
+            placeholder="Search by client name…"
+            value={search}
+            onValueChange={setSearch}
+          />
+          <CommandList>
+            <CommandEmpty>No interests found.</CommandEmpty>
+            <CommandGroup>
+              {options.map((i) => (
+                <CommandItem
+                  key={i.id}
+                  value={i.id}
+                  onSelect={() => {
+                    onChange(i.id);
+                    setOpen(false);
+                  }}
+                >
+                  <Check
+                    className={cn('mr-2 h-4 w-4', value === i.id ? 'opacity-100' : 'opacity-0')}
+                  />
+                  <span className="truncate">
+                    {i.clientName ?? `Interest ${i.id.slice(0, 8)}`}
+                    {i.pipelineStage ? (
+                      <span className="ml-2 text-xs text-muted-foreground">{i.pipelineStage}</span>
+                    ) : null}
+                  </span>
+                </CommandItem>
+              ))}
+            </CommandGroup>
+          </CommandList>
+        </Command>
+      </PopoverContent>
+    </Popover>
+  );
+}