fix(reports): exclude income from Cartes top movers (#253 regression)

/pr-review on #255 caught a cross-consumer regression: broadening
COMPARE_DELTA_SQL to surface income (this PR) also feeds getCartesSnapshot,
whose "top movers" card is a spending view (up = red). A salary rise would land
under "biggest increases" coloured red — inverted meaning.

Filter significantMovers to expense leaves ((category_type ?? "expense") ===
"expense"), mirroring ComparePeriodChart. The surviving expense output is
byte-identical to pre-#253. Add a Cartes regression test (an income category
with the biggest delta must not top the movers list) — the existing test mocked
the compare SQL without category types, so it stayed silently green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/services/reportService.cartes.test.ts

@@ -235,6 +235,33 @@ describe("getCartesSnapshot", () => {
     expect(snapshot.topMoversDown[0].categoryName).toBe("D3");
   });
 
+  it("excludes income from top movers so a salary rise is not a red 'increase' (#253)", async () => {
+    // Post-#253 COMPARE_DELTA_SQL surfaces income as a signed positive SUM, so
+    // revenue rows now reach getCartesSnapshot. Top movers is a spending view
+    // (up = red), so income must be filtered out — otherwise a salary jump tops
+    // "biggest increases" in red. The category metadata query types id 99 as
+    // income; the two expense movers are absent from it and default to expense.
+    const momRows = [
+      { category_id: 99, category_name: "Salaire", category_color: "#000", month_current_total: 5000, month_previous_total: 100, cumulative_current_total: 5000, cumulative_previous_total: 100 },
+      { category_id: 1, category_name: "Épicerie", category_color: "#000", month_current_total: 300, month_previous_total: 100, cumulative_current_total: 300, cumulative_previous_total: 100 },
+      { category_id: 2, category_name: "Resto", category_color: "#000", month_current_total: 100, month_previous_total: 400, cumulative_current_total: 100, cumulative_previous_total: 400 },
+    ];
+    routeSelect([
+      { match: "strftime('%Y-%m', date)", rows: [{ month: "2026-03", income: 5000, expenses: 400 }] },
+      { match: "ORDER BY ABS(month_current_total - month_previous_total) DESC", rows: momRows },
+      { match: "parent_id FROM categories", rows: [{ id: 99, name: "Salaire", color: null, type: "income", parent_id: null }] },
+    ]);
+
+    const snapshot = await getCartesSnapshot(2026, 3);
+    const upNames = snapshot.topMoversUp.map((m) => m.categoryName);
+    // Income excluded despite the biggest delta (+4900).
+    expect(upNames).not.toContain("Salaire");
+    // The biggest EXPENSE increase leads instead.
+    expect(snapshot.topMoversUp[0].categoryName).toBe("Épicerie");
+    // Expense decrease still surfaces.
+    expect(snapshot.topMoversDown[0].categoryName).toBe("Resto");
+  });
+
   it("computes YTD KPIs correctly when mode=ytd (sums Jan→refMonth of refYear)", async () => {
     // Reference = 2026-03, YTD = Jan + Feb + Mar of 2026.
     routeSelect([

src/services/reportService.ts

@@ -1170,12 +1170,20 @@ export async function getCartesSnapshot(
 
   // Top movers: biggest MoM increases / decreases. `momRows` now carries the
   // compare hierarchy (Issue #247) — skip the subtotal (`is_parent`) rows so a
-  // parent group can't double-count against its own leaves. The surviving leaves
+  // parent group can't double-count against its own leaves. Keep only EXPENSE
-  // are byte-identical to the previous flat output; the sort/slice below is
+  // leaves: since Issue #253 broadened COMPARE_DELTA_SQL to surface income (and
-  // unchanged. `momRows` are sorted by absolute delta already; filter out
+  // net transfers), momRows now also carries revenue rows — and this card is a
-  // near-zero noise and split by sign.
+  // spending view whose colours read "up = red" (more spending is bad), so a
+  // salary rise must not appear under "biggest increases" in red. Mirror the
+  // expense-only filter ComparePeriodChart uses. The surviving expense leaves
+  // are byte-identical to the pre-#253 flat output. `momRows` are sorted by
+  // absolute delta already; filter out near-zero noise and split by sign.
   const significantMovers = momRows.filter(
-    (r) => !r.is_parent && r.deltaAbs !== 0 && (r.previousAmount > 0 || r.currentAmount > 0),
+    (r) =>
+      !r.is_parent &&
+      (r.category_type ?? "expense") === "expense" &&
+      r.deltaAbs !== 0 &&
+      (r.previousAmount > 0 || r.currentAmount > 0),
   );
   // Project the richer CategoryDelta shape down to the narrower CartesTopMover
   // shape so the Cartes dashboard keeps its stable contract regardless of how