chore(lint): scope the analyzer by severity, drop redundant IncludeRules

PSScriptAnalyzerSettings.psd1

@@ -1,3 +1,11 @@
 @{
-    IncludeRules = @('*')
+    # Scope analysis to actionable severities, dropping Information-level noise.
+    #
+    # ParseError must be listed. It is how PSScriptAnalyzer reports a file it
+    # could not parse at all, and naming Severity without it silently hides
+    # syntax-broken files: a file with a missing brace reports zero findings
+    # under @('Error', 'Warning'). Microsoft's documentation states this
+    # directly -- "To suppress ParseErrors, don't include it as a value in the
+    # Severity parameter" -- which is exactly what must not happen to a lint gate.
+    Severity = @('ParseError', 'Error', 'Warning')
 }