Mutation check done on all accepted tasks; mutant fixes; dump filter in proxy

- skip sy-subrc lines and CDS type lengths; CDS literal mutants; mutate helper classes
- proxy: sap_short_dumps shows only dumps of the current run
- 26/26 tasks pass; results in docs/faz1-tasarim.md 11g

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014aUaQeLnwbb1zTpN7kHeat

tasks_gen/eval/G0004/mutation.json

@@ -0,0 +1,59 @@
+{
+ "task": "G0004",
+ "mutants": [
+  {
+   "object": "{{P}}STOCK_AGE",
+   "mutant": "line 55: = -> <> (eq)",
+   "status": "invalid",
+   "hidden": "0/0",
+   "failed_tests": []
+  },
+  {
+   "object": "{{P}}STOCK_AGE",
+   "mutant": "line 66: + -> - (arith)",
+   "status": "killed",
+   "hidden": "9/10",
+   "failed_tests": [
+    "TOTAL_GROUPS_BY_MATERIAL"
+   ]
+  },
+  {
+   "object": "{{P}}STOCK_AGE",
+   "mutant": "line 74: OR -> AND (logic)",
+   "status": "killed",
+   "hidden": "8/10",
+   "failed_tests": [
+    "INVALID_ROWS_ARE_IGNORED",
+    "TOTAL_IGNORES_INVALID_ROWS"
+   ]
+  },
+  {
+   "object": "{{P}}STOCK_AGE",
+   "mutant": "line 77: - -> + (arith)",
+   "status": "killed",
+   "hidden": "6/10",
+   "failed_tests": [
+    "BUCKET_BOUNDARIES",
+    "GROUPS_SUM_QUANTITY_AND_COUNT",
+    "RESULT_IS_SORTED",
+    "SINGLE_BATCH_BUCKET_01"
+   ]
+  },
+  {
+   "object": "{{P}}STOCK_AGE",
+   "mutant": "line 82: <= -> > (rel)",
+   "status": "killed",
+   "hidden": "6/10",
+   "failed_tests": [
+    "BUCKET_BOUNDARIES",
+    "GROUPS_SUM_QUANTITY_AND_COUNT",
+    "RESULT_IS_SORTED",
+    "SINGLE_BATCH_BUCKET_01"
+   ]
+  }
+ ],
+ "valid": 4,
+ "killed": 4,
+ "kill_rate": 1.0,
+ "ok": true
+}