feat(suppliers)!: full customers model - structured address + custom fields

The dodavatele modal is now an exact mirror of the customers modal
(minus the PDF field-order picker): Nazev+ARES, Ulice, Mesto+PSC, Zeme,
ICO+ARES, DIC, and the same "Vlastni pole" editor (maxWidth md).

Two migrations on sklad_suppliers:
- structured street/city/postal_code/country replace the free-text
  address blob (best-effort split: street / PSC regex / city)
- custom_fields LONGTEXT replaces contact_person/email/phone/notes;
  existing values are preserved as labeled custom fields

The encode/decode of the custom_fields blob is shared with customers
via the new utils/custom-fields.ts. The PO PDF supplier block renders
the structured address + custom-field lines like the customer block;
the supplier picker/detail selects and types follow. Legacy clients
sending the dropped keys are silently stripped (tested). Suppliers
list shows Ulice/Mesto instead of the dropped contact columns; search
covers name/ico/city.

BREAKING CHANGE: sklad_suppliers.address, contact_person, email,
phone, notes columns dropped (data migrated); deploy must run
prisma migrate deploy + generate.

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

src/routes/admin/issued-orders-pdf.ts

@@ -117,11 +117,12 @@ function buildAddressLines(
 }
 
 /**
- * Address block for the sklad_suppliers counterparty. Unlike customers (which
- * have structured street/city/postal columns), suppliers.address is a single
- * Text blob — split it on newlines into one rendered line each (a blob without
- * newlines renders as one line). IČO/DIČ come from the supplier's ico/dic
- * columns, prefixed with the same translated labels the customer block used.
+ * Address block for the sklad_suppliers counterparty — full customer model
+ * (structured street/city/postal_code/country + custom_fields JSON; the old
+ * dedicated address/contact columns were dropped 2026-06). IČO/DIČ come from
+ * the supplier's ico/dic columns, prefixed with the same translated labels
+ * the customer block uses; custom fields render as appended lines in array
+ * order (suppliers have no PDF field-order picker).
  */
 function buildSupplierLines(
   supplier: Record<string, unknown> | null,
@@ -130,14 +131,52 @@ function buildSupplierLines(
   if (!supplier) return { name: "", lines: [] };
   const name = String(supplier.name || "");
   const lines: string[] = [];
-  if (supplier.address) {
-    for (const part of String(supplier.address).split(/\r?\n/)) {
-      const line = part.trim();
-      if (line) lines.push(line);
-    }
-  }
+  if (supplier.street) lines.push(String(supplier.street));
+  const cityLine = [supplier.postal_code, supplier.city]
+    .filter(Boolean)
+    .map(String)
+    .join(" ")
+    .trim();
+  if (cityLine) lines.push(cityLine);
+  if (supplier.country) lines.push(String(supplier.country));
   if (supplier.ico) lines.push(`${tObj.ico}${supplier.ico}`);
   if (supplier.dic) lines.push(`${tObj.dic}${supplier.dic}`);
+
+  // Custom fields ("Vlastní pole") — same blob format as customers; malformed
+  // JSON degrades to no extra lines rather than failing the PDF.
+  if (supplier.custom_fields) {
+    let parsed: unknown;
+    try {
+      parsed =
+        typeof supplier.custom_fields === "string"
+          ? JSON.parse(supplier.custom_fields)
+          : supplier.custom_fields;
+    } catch {
+      parsed = null;
+    }
+    const fields =
+      parsed && typeof parsed === "object" && !Array.isArray(parsed)
+        ? ((parsed as Record<string, unknown>).fields as Array<{
+            name?: string;
+            value?: string;
+            showLabel?: boolean;
+          }>)
+        : Array.isArray(parsed)
+          ? (parsed as Array<{
+              name?: string;
+              value?: string;
+              showLabel?: boolean;
+            }>)
+          : [];
+    for (const f of fields ?? []) {
+      const value = (f?.value || "").trim();
+      if (!value) continue;
+      const label = (f?.name || "").trim();
+      lines.push(
+        f?.showLabel !== false && label ? `${label}: ${value}` : value,
+      );
+    }
+  }
   return { name, lines };
 }