refactor: enhance visual aids in README for Two-Sum and Add Two Numbers by improving diagram clarity and formatting

Author: kimi0230

docs/Leetcode/0001.Two-Sum/README_solution.md

@@ -79,13 +79,13 @@ func twoSum(nums []int, target int) []int {
     2. `i = 1, v = 2`：`complement = 4`。Map 只有 `{3: 0}`。存入 `{3: 0, 2: 1}`。
     3. `i = 2, v = 4`：`complement = 2`。Map 存在 `2`，索引為 `1`。
     4. 返回 `[1, 2]`。正確。
-- **關鍵狀態變遷**：
+**Visual Aid**:
 ```mermaid
 stateDiagram-v2
     [*] --> Start
     Start --> i0: i=0, v=3, Map={}
-    i0 --> i1: complement=3 not in Map, Map={3:0}
-    i1 --> i2: i=1, v=2, complement=4 not in Map, Map={3:0, 2:1}
+    i0 --> i1: complement=3 not in Map, Map={3-0}
+    i1 --> i2: i=1, v=2, complement=4 not in Map, Map={3-0, 2-1}
     i2 --> Found: i=2, v=4, complement=2 found in Map!
     Found --> [*]
 ```

docs/Leetcode/0002.Add-Two-Numbers/README_solution.md

@@ -141,12 +141,12 @@ func addTwoNumbers(l1 *ListNode, l2 *ListNode) *ListNode {
 ```mermaid
 stateDiagram-v2
     direction LR
-    [*] --> S1: "L1:[9], L2:[1], C:0"
-    S1 --> S2: "Sum:10, Carry:1, Node:0"
-    S2 --> S3: "L1:[9], L2:nil, C:1"
-    S3 --> S4: "Sum:10, Carry:1, Node:0"
-    S4 --> S5: "L1:nil, L2:nil, C:1"
-    S5 --> S6: "Sum:1, Carry:0, Node:1"
+    [*] --> S1: L1 [9], L2 [1], C 0
+    S1 --> S2: Sum 10, Carry 1, Node 0
+    S2 --> S3: L1 [9], L2 nil, C 1
+    S3 --> S4: Sum 10, Carry 1, Node 0
+    S4 --> S5: L1 nil, L2 nil, C 1
+    S5 --> S6: Sum 1, Carry 0, Node 1
     S6 --> [*]
 ```