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/G0025/mutation.json

@@ -0,0 +1,32 @@
+{
+ "task": "G0025",
+ "mutants": [
+  {
+   "object": "{{P}}I_PARTNER_ALL",
+   "mutant": "line 10: 'A' -> 'Z' (lit)",
+   "status": "killed",
+   "hidden": "4/7",
+   "failed_tests": [
+    "ONLY_IN_A",
+    "SAME_ID_TWICE",
+    "SOURCE_A_ROWS"
+   ]
+  },
+  {
+   "object": "{{P}}I_PARTNER_ALL",
+   "mutant": "line 18: 'B' -> 'Z' (lit)",
+   "status": "killed",
+   "hidden": "3/7",
+   "failed_tests": [
+    "NAME_AND_CITY",
+    "ONLY_IN_B",
+    "SAME_ID_TWICE",
+    "SOURCE_B_ROWS"
+   ]
+  }
+ ],
+ "valid": 2,
+ "killed": 2,
+ "kill_rate": 1.0,
+ "ok": true
+}