docs(r2-12): document 5 alarm operator CLI commands; fix StyleGuide product name; add minimal .editorconfig (07/U-3, 07/C-5)

- docs/Client.CLI.md: added ### ack / confirm / shelve / enable / disable sections
  (synopsis + options + example + expected output), each noting the AlarmAck LDAP-role
  gate and that --event-id comes from a prior `alarms` notification. Doc now covers all
  13 CLI commands (was 8). Overview operations list updated.
- StyleGuide.md: 'ScadaBridge' -> 'OtOpcUa' (header line 3) + the ScadaBridge:Timeout
  config-key example -> OpcUa:Timeout.
- .editorconfig (new, root): minimal code-style anchor; all C# analyzer rules at
  suggestion severity so nothing fails a TreatWarningsAsErrors build (verified: 808
  warnings unchanged from baseline, 0 errors).

.editorconfig

@@ -0,0 +1,25 @@
+# Minimal repo code-style anchor (R2-12 / 07/C-5). Documents the already-consistent
+# conventions; all C# analyzer rules are `suggestion` severity so nothing here can fail a
+# TreatWarningsAsErrors build.
+root = true
+
+[*]
+charset = utf-8
+insert_final_newline = true
+indent_style = space
+
+[*.{cs,csproj,props,targets}]
+indent_size = 4
+
+[*.cs]
+csharp_style_namespace_declarations = file_scoped:suggestion
+dotnet_naming_rule.private_fields_underscore.severity = suggestion
+dotnet_naming_rule.private_fields_underscore.symbols = private_fields
+dotnet_naming_rule.private_fields_underscore.style = underscore_camel
+dotnet_naming_symbols.private_fields.applicable_kinds = field
+dotnet_naming_symbols.private_fields.applicable_accessibilities = private
+dotnet_naming_style.underscore_camel.capitalization = camel_case
+dotnet_naming_style.underscore_camel.required_prefix = _
+
+[*.{yml,yaml,json}]
+indent_size = 2