feat: NAS storage for invoices/offers, code cleanup, date/time fixes

- NAS storage for created invoices (PDF via puppeteer), received invoices,
  and offers with auto-save on create/edit
- Deterministic file paths derived from DB fields (no file_path column needed)
- Separate NAS mount points: NAS_FINANCIALS_PATH, NAS_OFFERS_PATH
- Invoice language field (cs/en) stored per invoice, replaces lang modal
- Invoices list filtered by month/year matching KPI card selection
- Centralized date helpers (src/utils/date.ts) replacing all .toISOString()
  calls that returned UTC instead of local time
- Attendance project switching uses exact time (not rounded)
- Comment cleanup: removed ~100 unnecessary/Czech comments
- Removed as-any casts in orders and attendance
- Prisma migrations: add invoice language, drop received_invoices BLOB columns

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/routes/admin/scope-templates.ts

@@ -27,7 +27,6 @@ export default async function scopeTemplatesRoutes(
       const query = request.query as Record<string, unknown>;
       const action = query.action ? String(query.action) : null;
 
-      // Item templates
       if (action === "items") {
         const items = await prisma.item_templates.findMany({
           where: { is_deleted: false },
@@ -70,7 +69,6 @@ export default async function scopeTemplatesRoutes(
           category: body.category ? String(body.category) : null,
         };
 
-        // Update existing item if id is provided
         if (body.id) {
           const existingItem = await prisma.item_templates.findUnique({
             where: { id: Number(body.id) },
@@ -92,7 +90,6 @@ export default async function scopeTemplatesRoutes(
         return success(reply, { id: item.id }, 201, "Položka byla vytvořena");
       }
 
-      // Scope template create (original logic below)
       const scopeParsed = parseBody(CreateScopeTemplateSchema, request.body);
       if ("error" in scopeParsed) return error(reply, scopeParsed.error, 400);
       const body = scopeParsed.data;