fix(telemetry): drop unmeasurable Queue Bypass Ratio panel

The Transaction Overview panel "Queue Bypass Ratio (Direct Apply vs
Enqueue)" reported a confident 0.50 on every node while the true bypass
rate was zero. The two spans it divided are not disjoint alternatives:
txq.apply_direct is a child of txq.enqueue. TxQ.cpp creates the
apply_direct span as the first statement of tryDirectApply(), ahead of
the account, sequence and fee-level guards, and tryDirectApply() is
called from inside the live enqueue scope. The span therefore counts
attempts, so the denominator direct + enqueue counts each transaction
twice and pins the ratio to one half algebraically.

Measured on a four-node fleet: 6082443 direct against 6082877 enqueue
over the same population, panel output 0.5000170 on three nodes and
0.5000000 on the fourth. Grouping txq.enqueue by txq_status over seven
days returns only "rejected" -- no transaction has ever taken the
direct-apply path.

Remove the panel rather than repoint it. A correct expression using
txq_status as the disjoint discriminator would render permanently
empty on this fleet, which reads no better than a wrong number.

Widen the band partner "TxQ Enqueue Rate by Transaction Type" from 12
to 24 columns so the y=48 band still fills the grid. Every band in all
ten dashboards sums to 24 columns; leaving a half-width hole would be
the only exception. Panel order and every other panel's position,
width and height are unchanged.

The runbook already listed txq.apply_direct as available but not
paneled, so that row becomes accurate. Rows describing the span itself
are untouched -- the span and its metric are unchanged.

docker/telemetry/grafana/dashboards/transaction-overview.json

@@ -555,7 +555,7 @@
       "type": "timeseries",
       "gridPos": {
         "h": 8,
-        "w": 12,
+        "w": 24,
         "x": 0,
         "y": 48
       },
@@ -589,46 +589,6 @@
         "overrides": []
       }
     },
-    {
-      "title": "Queue Bypass Ratio (Direct Apply vs Enqueue)",
-      "description": "**What:** Fraction of transactions that applied straight to the open ledger versus those that had to be queued.\n**How it's computed:** Ratio of direct applies to direct-plus-queued over a 5-minute window, per node.\n**Reading it:** A high fraction means the network is keeping up without escalation.\n**Healthy range:** Near 1.0 in normal conditions.\n**Watch for:** A falling fraction is the cleanest single signal the network has entered sustained fee escalation.\n**Source:** src/xrpld/app/misc/detail/TxQ.cpp:TxQ::tryDirectApply, TxQ::apply",
-      "type": "timeseries",
-      "gridPos": {
-        "h": 8,
-        "w": 12,
-        "x": 12,
-        "y": 48
-      },
-      "options": {
-        "tooltip": {
-          "mode": "multi",
-          "sort": "desc",
-          "maxHeight": 600
-        }
-      },
-      "targets": [
-        {
-          "datasource": {
-            "type": "prometheus"
-          },
-          "expr": "sum by (service_instance_id) (rate(traces_span_metrics_calls_total{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", span_name=\"txq.apply_direct\"}[5m])) / clamp_min(sum by (service_instance_id) (rate(traces_span_metrics_calls_total{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", span_name=\"txq.apply_direct\"}[5m])) + sum by (service_instance_id) (rate(traces_span_metrics_calls_total{service_instance_id=~\"$node\", deployment_environment=~\"$deployment_environment\", xrpl_network_type=~\"$xrpl_network_type\", service_name=~\"$service_name\", span_name=\"txq.enqueue\"}[5m])), 1)",
-          "legendFormat": "Direct-Apply Fraction [{{service_instance_id}}]"
-        }
-      ],
-      "fieldConfig": {
-        "defaults": {
-          "unit": "percentunit",
-          "custom": {
-            "axisLabel": "Bypass Fraction",
-            "spanNulls": 1800000,
-            "insertNulls": false,
-            "showPoints": "auto",
-            "pointSize": 3
-          }
-        },
-        "overrides": []
-      }
-    },
     {
       "title": "Queue Accept (Drain) Duration per Ledger",
       "description": "**What:** Time spent draining queued transactions into a newly closed ledger.\n**How it's computed:** 95th and 50th percentile of per-ledger drain durations over a 5-minute window, per node.\n**Reading it:** Rises as the queue holds more transactions to process at close.\n**Healthy range:** A few milliseconds when the queue is light.\n**Watch for:** Rising drain time signals queue pressure at ledger close.\n**Source:** src/xrpld/app/misc/detail/TxQ.cpp:TxQ::accept",