exceptions: move flow memcap stats to common counter

Part of making the exception policy stats counters more search
friendly.

Task #7185

(cherry picked from commit 0f81190d2a)

etc/schema.json

@@ -4958,6 +4958,14 @@
                                         "How many times defrag memcap exception policy was applied, and which one",
                                 "$ref": "#/$defs/exceptionPolicy"
                             }
+                        },
+                        "flow": {
+                            "type": "object",
+                            "memcap": {
+                                "description":
+                                        "How many times flow memcap exception policy was applied, and which one",
+                                "$ref": "#/$defs/exceptionPolicy"
+                            }
                         }
                     }
                 },
@@ -5012,11 +5020,6 @@
                         "memcap": {
                             "type": "integer"
                         },
-                        "memcap_exception_policy": {
-                            "description":
-                                    "How many times flow memcap exception policy was applied, and which one",
-                            "$ref": "#/$defs/exceptionPolicy"
-                        },
                         "memuse": {
                             "type": "integer"
                         },

src/decode.c

@@ -644,7 +644,7 @@ void DecodeRegisterPerfCounters(DecodeThreadVars *dtv, ThreadVars *tv)
     dtv->counter_nsh = StatsRegisterMaxCounter("decoder.nsh", tv);
     dtv->counter_flow_memcap = StatsRegisterCounter("flow.memcap", tv);
     ExceptionPolicySetStatsCounters(tv, &dtv->counter_flow_memcap_eps, &flow_memcap_eps_stats,
-            FlowGetMemcapExceptionPolicy(), "flow.memcap_exception_policy.",
+            FlowGetMemcapExceptionPolicy(), "exception_policy.flow.memcap.",
             IsFlowMemcapExceptionPolicyStatsValid);
 
     dtv->counter_tcp_active_sessions = StatsRegisterCounter("tcp.active_sessions", tv);