fix(telemetry): add missing span constants, fix test API, update levelization

Add unknownCommand and wsUpgrade span name constants to RpcSpanNames.h,
fix SpanGuardFactory tests to use the 3-argument SpanGuard::span() API,
update levelization results, and apply rename script to docs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/scripts/levelization/results/loops.txt

@@ -5,7 +5,7 @@ Loop: test.jtx test.unit_test
   test.unit_test ~= test.jtx
 
 Loop: xrpl.telemetry xrpld.rpc
-  xrpld.rpc ~= xrpl.telemetry
+  xrpld.rpc > xrpl.telemetry
 
 Loop: xrpld.app xrpld.overlay
   xrpld.app > xrpld.overlay

.github/scripts/levelization/results/ordering.txt

@@ -194,6 +194,7 @@ tests.libxrpl > xrpl.json
 tests.libxrpl > xrpl.net
 tests.libxrpl > xrpl.protocol
 tests.libxrpl > xrpl.protocol_autogen
+tests.libxrpl > xrpl.telemetry
 xrpl.conditions > xrpl.basics
 xrpl.conditions > xrpl.protocol
 xrpl.core > xrpl.basics