feat(rental): add inventory and condition reports (#7)

frontend/src/app/components/inventory-page/inventory-page.css

@@ -0,0 +1,16 @@
+.inventory-line {
+  margin: 1rem 0;
+}
+.inventory-line label {
+  display: block;
+  margin: 0.5rem 0;
+}
+.inventory-line span {
+  display: block;
+}
+.inventory-line input,
+.inventory-line select,
+.inventory-line textarea {
+  max-width: 32rem;
+  width: 100%;
+}