feat: new task

tasks/space-exploration/docs/space-exploration-4.md

@@ -0,0 +1,54 @@
+# Space Exploration 4
+
+**Title:** Исследуй Планету
+**Subtitle:** Собери ресурсы, решая примеры!
+**Footer bubble:** Итого собрано ресурсов:
+
+## Layout
+
+- 2 columns, 20 problems per page
+- Icons: pack1 (pages 1–6), pack2 (pages 7–9)
+
+## Problem Pattern
+
+A ± B, where:
+- B is from 1 to 10
+- Result is from 1 to 29
+- Each problem crosses a 10-boundary: either 10 or 20 (strictly, not just touching)
+
+Types:
+- Add crossing 10: A ∈ [1,9], B such that A+B ∈ [11,29]
+- Add crossing 20: A ∈ [11,19], B such that A+B ∈ [21,29]
+- Sub crossing 10: A ∈ [11,19], B such that A−B ∈ [1,9]
+- Sub crossing 20: A ∈ [21,29], B such that A−B ∈ [11,19]
+
+All 4 types are mixed randomly on every page.
+
+## Pages
+
+### Page 1 (pack1)
+- **Hero:** spaceship1.jpeg, direction: row-reverse
+
+### Page 2 (pack1)
+- **Hero:** spaceship2.jpeg, direction: row
+
+### Page 3 (pack1)
+- **Hero:** spaceship3.png, direction: row-reverse
+
+### Page 4 (pack1)
+- **Hero:** spaceship4.jpeg, direction: row
+
+### Page 5 (pack1)
+- **Hero:** spaceship5.jpeg, direction: row-reverse
+
+### Page 6 (pack1)
+- **Hero:** spaceship6.jpeg, direction: row
+
+### Page 7 (pack2)
+- **Hero:** spaceship7.jpeg, direction: row-reverse
+
+### Page 8 (pack2)
+- **Hero:** spaceship8.jpeg, direction: row
+
+### Page 9 (pack2)
+- **Hero:** spaceship9.jpeg, direction: row-reverse