docs: add XML doc comments across src + Sister Projects section in CLAUDE.md

Bulk CommentChecker pass: fills in <param>/<inheritdoc> tags on public
APIs across all 23 src/ projects so the doc-coverage gate is green. Also
adds a Sister Projects section to CLAUDE.md pointing at the MxAccess
Gateway and OtOpcUa sibling repos, and gitignores local credential
captures (*login*.txt) and the wonder-app-vd03 deploy/ artifacts.

src/ScadaLink.TemplateEngine/Validation/ValidationService.cs

@@ -22,6 +22,11 @@ public class ValidationService
     private readonly SemanticValidator _semanticValidator;
     private readonly ScriptCompiler _scriptCompiler;
 
+    /// <summary>
+    /// Initializes a new instance of the ValidationService with the specified dependencies.
+    /// </summary>
+    /// <param name="semanticValidator">The semantic validator for configuration validation.</param>
+    /// <param name="scriptCompiler">The script compiler for validating script code.</param>
     public ValidationService(SemanticValidator semanticValidator, ScriptCompiler scriptCompiler)
     {
         _semanticValidator = semanticValidator;
@@ -38,6 +43,8 @@ public class ValidationService
     /// <summary>
     /// Runs the full validation pipeline on a flattened configuration.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
+    /// <param name="sharedScripts">Optional list of shared scripts for validation context.</param>
     public ValidationResult Validate(FlattenedConfiguration configuration, IReadOnlyList<ResolvedScript>? sharedScripts = null)
     {
         ArgumentNullException.ThrowIfNull(configuration);
@@ -60,6 +67,7 @@ public class ValidationService
     /// <summary>
     /// Validates that flattening produced a non-empty configuration.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateFlatteningSuccess(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -88,6 +96,7 @@ public class ValidationService
     /// Validates that there are no naming collisions across entity types.
     /// Canonical names must be unique within their entity type (attributes, alarms, scripts).
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateNamingCollisions(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -104,6 +113,7 @@ public class ValidationService
     /// <summary>
     /// Validates that all scripts compile successfully using the ScriptCompiler.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public ValidationResult ValidateScriptCompilation(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -127,6 +137,7 @@ public class ValidationService
     /// Validates that alarm trigger configurations reference existing attributes.
     /// Alarm trigger configs are JSON with an "attributeName" field referencing a canonical attribute name.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateAlarmTriggerReferences(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -155,6 +166,7 @@ public class ValidationService
     /// <summary>
     /// Validates that script trigger configurations reference existing attributes.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateScriptTriggerReferences(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -196,6 +208,7 @@ public class ValidationService
     ///     <see cref="ValidateScriptTriggerReferences"/> for the structured triggers.</item>
     /// </list>
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateExpressionTriggers(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -288,6 +301,7 @@ public class ValidationService
     /// Reads the "expression" string from a <c>{ "expression": "..." }</c> trigger
     /// configuration. Returns <c>null</c> on malformed JSON or a missing key.
     /// </summary>
+    /// <param name="triggerConfigJson">The trigger configuration JSON to parse.</param>
     internal static string? ExtractExpressionFromTriggerConfig(string? triggerConfigJson)
     {
         if (string.IsNullOrWhiteSpace(triggerConfigJson))
@@ -315,6 +329,7 @@ public class ValidationService
     /// brackets/quotes. Returns an error message, or <c>null</c> when the expression
     /// looks well-formed.
     /// </summary>
+    /// <param name="expression">The expression to check for syntax errors.</param>
     internal static string? CheckExpressionSyntax(string expression)
     {
         // Advisory forbidden-API scan (TemplateEngine-006): code-region-aware so
@@ -423,6 +438,7 @@ public class ValidationService
     /// Best-effort: only matches double-quoted literals (the form the editor emits)
     /// and skips keys built dynamically.
     /// </summary>
+    /// <param name="expression">The expression to scan for attribute references.</param>
     internal static IEnumerable<string> ExtractAttributeReferences(string expression)
     {
         var seen = new HashSet<string>(StringComparer.Ordinal);
@@ -473,6 +489,7 @@ public class ValidationService
     /// <summary>
     /// Validates that all data-sourced attributes have connection bindings.
     /// </summary>
+    /// <param name="configuration">The flattened configuration to validate.</param>
     public static ValidationResult ValidateConnectionBindingCompleteness(FlattenedConfiguration configuration)
     {
         var errors = new List<ValidationEntry>();
@@ -510,6 +527,10 @@ public class ValidationService
         }
     }
 
+    /// <summary>
+    /// Extracts the attribute name from a trigger configuration JSON.
+    /// </summary>
+    /// <param name="triggerConfigJson">The trigger configuration JSON to parse.</param>
     internal static string? ExtractAttributeNameFromTriggerConfig(string triggerConfigJson)
     {
         // Accept both keys to stay consistent with FlatteningService.PrefixTriggerAttribute,
@@ -536,6 +557,7 @@ public class ValidationService
     /// all-nulls on malformed JSON — callers should treat that as "nothing to
     /// validate" and let other checks surface the deeper problem.
     /// </summary>
+    /// <param name="triggerConfigJson">The trigger configuration JSON to parse.</param>
     internal static HiLoSetpoints ExtractHiLoSetpoints(string triggerConfigJson)
     {
         try