refactor: tighten types and reuse instrument UI

src/pages/account/model/positions.test.ts

@@ -59,13 +59,13 @@ describe("account position sections", () => {
 			"bonds",
 			"other",
 		]);
-		expect(sections[2].groups.map(group => group.positions[0].figi)).toEqual([
+		expect(sections[2]?.groups.map(group => group.positions[0].figi)).toEqual([
 			"FIGI-FUND",
 			...otherTypes.map(type => `FIGI-${type}-NEXT`),
 		]);
-		expect(sections[0].groups[0].positions[0].shareText).toBe("40 %");
-		expect(sections[1].groups[0].positions[0].shareText).toBe("20 %");
-		expect(sections[2].groups[1].positions[0].shareText).toBe("20 %");
+		expect(sections[0]?.groups[0]?.positions[0].shareText).toBe("40 %");
+		expect(sections[1]?.groups[0]?.positions[0].shareText).toBe("20 %");
+		expect(sections[2]?.groups[1]?.positions[0].shareText).toBe("20 %");
 		expect(snapshot).toEqual(original);
 	});
 
@@ -125,10 +125,10 @@ describe("account position sections", () => {
 					figi: null,
 				},
 				{ ...second, figi: null },
-			])[0].groups,
+			])[0]?.groups,
 		).toHaveLength(1);
 		expect(
-			sections([position, { ...second, figi: "OTHER-FIGI" }])[0].groups,
+			sections([position, { ...second, figi: "OTHER-FIGI" }])[0]?.groups,
 		).toHaveLength(2);
 		expect(
 
@@ -143,19 +143,19 @@ describe("account position sections", () => {
 					figi: null,
 					isin: null,
 				},
-			])[0].groups,
+			])[0]?.groups,
 		).toHaveLength(2);
 	});
 
 	it("preserves one-account cards and does not merge repeated rows on the same account", () => {
 		expect(
-			sections([position, { ...second, account: position.account }])[0].groups,
+			sections([position, { ...second, account: position.account }])[0]?.groups,
 		).toHaveLength(2);
 		expect(
 			sections([
 				{ ...position, account: undefined },
 				{ ...second, account: undefined },
-			])[0].groups,
+			])[0]?.groups,
 		).toHaveLength(2);
 	});
 
@@ -170,9 +170,9 @@ describe("account position sections", () => {
 		];
 
 		const before = structuredClone(source);
-		const [group] = sections(source)[0].groups;
+		const group = sections(source)[0]?.groups[0];
 		expect(
-			group.positions.map(item => [
+			group?.positions.map(item => [
 				item.quantity,
 				item.currentValue,
 				item.averagePurchasePrice,