feat: deepen skill test coverage — 52 → 247 cases across all 43 skills

Add 195 new test cases covering examples from SKILL.md, edge cases,
and parameter combinations. Create _skill.json for form-edit, skd-edit,
subsystem-edit. Add fixtures for negative validate cases. Fix
normalizeUuids in meta-validate/meta-info configs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/skills/cases/skd-validate/fixtures/empty-field/Template.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<DataCompositionSchema xmlns="http://v8.1c.ru/8.1/data-composition-system/schema"
+    xmlns:dcscom="http://v8.1c.ru/8.1/data-composition-system/common"
+    xmlns:dcscor="http://v8.1c.ru/8.1/data-composition-system/core"
+    xmlns:dcsset="http://v8.1c.ru/8.1/data-composition-system/settings"
+    xmlns:v8="http://v8.1c.ru/8.1/data/core"
+    xmlns:v8ui="http://v8.1c.ru/8.1/data/ui"
+    xmlns:xs="http://www.w3.org/2001/XMLSchema"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <dataSource>
+    <name>ИсточникДанных1</name>
+    <dataSourceType>Local</dataSourceType>
+  </dataSource>
+  <dataSet xsi:type="DataSetQuery">
+    <name>Основной</name>
+    <dataSource>ИсточникДанных1</dataSource>
+    <query>SELECT 1</query>
+    <field xsi:type="DataSetFieldField">
+      <dataPath></dataPath>
+      <field></field>
+    </field>
+  </dataSet>
+  <settingsVariant>
+    <dcsset:name>Основной</dcsset:name>
+    <dcsset:settings/>
+  </settingsVariant>
+</DataCompositionSchema>