[FIR] Add kind for back edges in CFG

compiler/fir/analysis-tests/testData/resolve/cfg/complex.dot

@@ -260,7 +260,7 @@ digraph complex_kt {
     79 -> {68} [style=dotted];
     80 -> {68};
     81 -> {82};
-    82 -> {58};
+    82 -> {58} [color=green style=dashed];
     83 -> {84};
     84 -> {52};
     84 -> {85} [style=dotted];

compiler/fir/analysis-tests/testData/resolve/cfg/jumps.dot

@@ -191,7 +191,7 @@ digraph jumps_kt {
     63 -> {64} [style=dotted];
     64 -> {65} [style=dotted];
     65 -> {66} [style=dotted];
-    66 -> {56} [style=dotted];
+    66 -> {56} [color=green style=dotted];
     67 -> {68};
     68 -> {53};
 
@@ -241,7 +241,8 @@ digraph jumps_kt {
     80 -> {81} [style=dotted];
     81 -> {82} [style=dotted];
     82 -> {83} [style=dotted];
-    83 -> {73 72} [style=dotted];
+    83 -> {72} [style=dotted];
+    83 -> {73} [color=green style=dotted];
     84 -> {85};
     85 -> {70};
 
@@ -307,14 +308,14 @@ digraph jumps_kt {
     99 -> {100 106};
     100 -> {101};
     101 -> {102};
-    102 -> {88};
     102 -> {103} [style=dotted];
+    102 -> {88} [color=green style=dashed];
     103 -> {104} [style=dotted];
     104 -> {105} [style=dotted];
     105 -> {96} [style=dotted];
     106 -> {96};
     107 -> {108};
-    108 -> {90};
+    108 -> {90} [color=green style=dashed];
 
     subgraph cluster_30 {
         color=red
@@ -346,8 +347,8 @@ digraph jumps_kt {
     115 -> {116};
     116 -> {113};
     117 -> {118 119};
-    118 -> {117};
     118 -> {115} [color=green];
+    118 -> {117} [color=green style=dashed];
     119 -> {118};
     119 -> {120} [style=dotted];
     120 -> {118} [style=dotted];

compiler/fir/analysis-tests/testData/resolve/cfg/lambdas.dot

@@ -64,8 +64,8 @@ digraph lambdas_kt {
     17 -> {6};
     18 -> {6};
     19 -> {20 21};
-    20 -> {19};
     20 -> {14} [color=green];
+    20 -> {19} [color=green style=dashed];
     21 -> {22};
     22 -> {20};
 
@@ -166,8 +166,8 @@ digraph lambdas_kt {
     52 -> {53} [style=dotted];
     53 -> {48} [style=dotted];
     54 -> {55 56};
-    55 -> {54};
     55 -> {50} [color=green];
+    55 -> {54} [color=green style=dashed];
     56 -> {57};
     57 -> {48};
     57 -> {58} [style=dotted];
@@ -203,8 +203,8 @@ digraph lambdas_kt {
     64 -> {65} [style=dotted];
     65 -> {60} [style=dotted];
     66 -> {67 68};
-    67 -> {66};
     67 -> {62} [color=green];
+    67 -> {66} [color=green style=dashed];
     68 -> {69};
     69 -> {60};
     69 -> {70} [style=dotted];

compiler/fir/analysis-tests/testData/resolve/cfg/localClassesWithImplicit.dot

@@ -184,8 +184,8 @@ digraph localClassesWithImplicit_kt {
     31 -> {32} [style=dotted];
     32 -> {27} [style=dotted];
     33 -> {34 35};
-    34 -> {33};
     34 -> {29} [color=green];
+    34 -> {33} [color=green style=dashed];
     35 -> {36};
     36 -> {37};
     37 -> {39};
@@ -217,8 +217,8 @@ digraph localClassesWithImplicit_kt {
     62 -> {63} [style=dotted];
     63 -> {58} [style=dotted];
     64 -> {65 66};
-    65 -> {64};
     65 -> {60} [color=green];
+    65 -> {64} [color=green style=dashed];
     66 -> {67};
     67 -> {68};
     68 -> {69};
@@ -320,8 +320,8 @@ digraph localClassesWithImplicit_kt {
     86 -> {87} [style=dotted];
     87 -> {82} [style=dotted];
     88 -> {89 90};
-    89 -> {88};
     89 -> {84} [color=green];
+    89 -> {88} [color=green style=dashed];
     90 -> {91};
     91 -> {92};
     92 -> {94};
@@ -379,8 +379,8 @@ digraph localClassesWithImplicit_kt {
     117 -> {118} [style=dotted];
     118 -> {113} [style=dotted];
     119 -> {120 121};
-    120 -> {119};
     120 -> {115} [color=green];
+    120 -> {119} [color=green style=dashed];
     121 -> {122};
     122 -> {123};
     123 -> {124};

compiler/fir/analysis-tests/testData/resolve/cfg/loops.dot

@@ -46,7 +46,7 @@ digraph loops_kt {
     10 -> {11};
     11 -> {12};
     12 -> {13};
-    13 -> {4};
+    13 -> {4} [color=green style=dashed];
     14 -> {15};
     15 -> {1};
 
@@ -93,7 +93,8 @@ digraph loops_kt {
     26 -> {27};
     27 -> {28};
     28 -> {29};
-    29 -> {20 19};
+    29 -> {19};
+    29 -> {20} [color=green style=dashed];
     30 -> {31};
     31 -> {17};
 
@@ -158,7 +159,7 @@ digraph loops_kt {
     51 -> {52};
     52 -> {53};
     53 -> {54};
-    54 -> {41};
+    54 -> {41} [color=green style=dashed];
     55 -> {56};
     56 -> {33};
 
@@ -201,7 +202,7 @@ digraph loops_kt {
     65 -> {66};
     66 -> {67};
     67 -> {68};
-    68 -> {61};
+    68 -> {61} [color=green style=dashed];
     69 -> {58} [style=dotted];
 
     subgraph cluster_20 {
@@ -275,7 +276,7 @@ digraph loops_kt {
     89 -> {80} [style=dotted];
     90 -> {80};
     91 -> {92};
-    92 -> {74};
+    92 -> {74} [color=green style=dashed];
     93 -> {71};
 
     subgraph cluster_28 {
@@ -317,7 +318,7 @@ digraph loops_kt {
     102 -> {103} [style=dotted];
     103 -> {104} [style=dotted];
     104 -> {105} [style=dotted];
-    105 -> {98} [style=dotted];
+    105 -> {98} [color=green style=dotted];
     106 -> {95};
 
     subgraph cluster_33 {
@@ -358,8 +359,8 @@ digraph loops_kt {
     115 -> {116};
     116 -> {117};
     117 -> {118};
-    118 -> {111};
     118 -> {110} [style=dotted];
+    118 -> {111} [color=green style=dashed];
     119 -> {108} [style=dotted];
 
     subgraph cluster_38 {
@@ -432,8 +433,8 @@ digraph loops_kt {
     139 -> {140};
     140 -> {141};
     141 -> {142};
-    142 -> {124};
     142 -> {123} [style=dotted];
+    142 -> {124} [color=green style=dashed];
     143 -> {121};
 
     subgraph cluster_46 {
@@ -475,7 +476,7 @@ digraph loops_kt {
     153 -> {154};
     154 -> {155};
     155 -> {147};
-    155 -> {148} [style=dotted];
+    155 -> {148} [color=green style=dotted];
     156 -> {145};
 
 }

compiler/fir/analysis-tests/testData/resolve/cfg/postponedLambdas.dot

@@ -34,8 +34,8 @@ digraph postponedLambdas_kt {
     7 -> {8};
     8 -> {3};
     9 -> {10 11};
-    10 -> {9};
     10 -> {6} [color=green];
+    10 -> {9} [color=green style=dashed];
     11 -> {10};
 
 }

compiler/fir/analysis-tests/testData/resolve/cfg/propertiesAndInitBlocks.dot

@@ -177,8 +177,8 @@ digraph propertiesAndInitBlocks_kt {
     67 -> {64};
     20 -> {21 22};
     20 -> {26 35 38} [color=red];
-    21 -> {20};
     21 -> {66} [color=green];
+    21 -> {20} [color=green style=dashed];
     22 -> {23};
     23 -> {24};
     24 -> {64};

compiler/fir/analysis-tests/testData/resolve/cfg/tryCatch.dot

@@ -280,8 +280,8 @@ digraph tryCatch_kt {
     79 -> {80};
     80 -> {47};
     81 -> {82};
-    82 -> {39};
     82 -> {83} [style=dotted];
+    82 -> {39} [color=green style=dashed];
     83 -> {84} [style=dotted];
     84 -> {85} [style=dotted];
     85 -> {47} [style=dotted];
@@ -294,7 +294,7 @@ digraph tryCatch_kt {
     91 -> {92};
     92 -> {93};
     93 -> {94};
-    94 -> {41};
+    94 -> {41} [color=green style=dashed];
     95 -> {96};
     96 -> {38};