CLDR-17971 kbd: (dtd/spec) add <info attribution=…> attribute (#4360)

Author: srl295

docs/ldml/tr35-keyboards.md

@@ -872,7 +872,8 @@ Element containing informative properties about the layout, for displaying in us
       name="…name"
       author="…author"
       layout="…hint of the layout"
-      indicator="…short identifier" />
+      indicator="…short identifier"
+      attribution="…attribution" />
 ```
 
 > <small>
@@ -901,17 +902,21 @@ _Attribute:_ `name` (required)
 
 * * *
 
-
 _Attribute:_ `author`
 
 > The `author` attribute value contains the name of the author of the layout file.
+> There is no requirement that an implementation display, store, or otherwise process this informative attribute.
+
+* * *
 
 _Attribute:_ `layout`
 
 > The `layout` attribute describes the layout pattern, such as QWERTY, DVORAK, INSCRIPT, etc. typically used to distinguish various layouts for the same language.
 >
 > This attribute is not localized, but is an informative identifier for implementation use.
 
+* * *
+
 _Attribute:_ `indicator`
 
 > The `indicator` attribute describes a short string to be used in currently selected layout indicator, such as `US`, `SI9` etc.
@@ -921,6 +926,21 @@ _Attribute:_ `indicator`
 
 * * *
 
+_Attribute:_ `attribution`
+
+> The `attribution` attribute describes a short string which gives some indication of the originating entity of the keyboard design, if different from the author of the layout file.
+> For example, an external standards body or other entity may have originated the layout used in the document.
+> This attribute does not imply endorsement by the named entity.
+>
+> This attribute is not localized.
+> There is no requirement that an implementation display, store, or otherwise process this attribute.
+
+```xml
+<info attribution="Malta Standards Authority"/>
+```
+
+* * *
+
 ### Element: settings
 
 An element used to keep track of layout-specific settings by implementations. This element may or may not show up on a layout. These settings reflect the normal practice by the implementation. However, an implementation using the data may customize the behavior.

keyboards/3.0/mt-t-k0-47key.xml

@@ -1,15 +1,25 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-  Note: conformsTo= references a previous release here,
-  because this keyboard does not depend on schema or data from later CLDR versions.
+  Note: conformsTo= may reference a previous release,
+  if this keyboard does not depend on schema or data from later CLDR versions.
 -->
-<keyboard3 xmlns="https://schemas.unicode.org/cldr/45/keyboard3" locale="mt-t-k0-47key" conformsTo="45">
+<keyboard3
+    xmlns="https://schemas.unicode.org/cldr/47/keyboard3"
+    locale="mt-t-k0-47key"
+    conformsTo="47">
+
     <locales>
         <!-- English is also an official language in Malta.-->
         <locale id="en" />
     </locales>
-    <info name="Maltese 47-key" author="Steven R. Loomis" layout="QWERTY" indicator="MT" />
-    <!-- MSA 100:2002 -->
+
+    <info
+        name="Malti (47-key, MSA 100-2002)"
+        author="Steven R. Loomis"
+        layout="QWERTY"
+        indicator="MT"
+        attribution="Malta Standards Authority"
+    />
 
     <keys>
         <!-- imports -->

keyboards/3.0/mt.xml

@@ -1,20 +1,27 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-Copyright © 1991-2024 Unicode, Inc.
+Copyright © 1991-2025 Unicode, Inc.
 SPDX-License-Identifier: Unicode-3.0
 CLDR data files are interpreted according to the LDML specification (http://unicode.org/reports/tr35/)
 -->
 <!--
-  Note: conformsTo= references a previous release here,
-  because this keyboard does not depend on schema or data from later CLDR versions.
+  Note: conformsTo= may reference a previous release,
+  if this keyboard does not depend on schema or data from later CLDR versions.
 -->
-<keyboard3 xmlns="https://schemas.unicode.org/cldr/45/keyboard3" locale="mt" conformsTo="45">
+<keyboard3 xmlns="https://schemas.unicode.org/cldr/47/keyboard3" locale="mt" conformsTo="47">
+
     <locales>
         <!-- English is also an official language in Malta.-->
         <locale id="en" />
     </locales>
-    <info name="Maltese" author="Steven R. Loomis" layout="QWERTY" indicator="MT" />
-    <!-- MSA 100:2002 -->
+
+    <info
+        name="Malti (48-key, MSA 100:2002)"
+        author="Steven R. Loomis"
+        layout="QWERTY"
+        indicator="MT"
+        attribution="Malta Standards Authority"
+    />
 
     <keys>
         <!-- imports -->
@@ -47,7 +54,7 @@ CLDR data files are interpreted according to the LDML specification (http://unic
         <key id="c-cedilla" output="ç" />
     </keys>
 
-     <!-- 48-key -->
+    <!-- 48-key -->
     <layers formId="iso">
         <layer modifiers="none">
             <row keys="c-tikka 1 2 3 4 5 6 7 8 9 0 hyphen equal" />

keyboards/dtd/ldmlKeyboard3.dtd

@@ -51,6 +51,9 @@ CLDR data files are interpreted according to the LDML specification (http://unic
 <!ATTLIST info indicator CDATA #IMPLIED >
     <!--@MATCH:any-->
     <!--@VALUE-->
+<!ATTLIST info attribution CDATA #IMPLIED >
+    <!--@MATCH:any-->
+    <!--@VALUE-->
 
 <!ELEMENT settings EMPTY >
     <!--@ORDERED-->

keyboards/dtd/ldmlKeyboard3.xsd

@@ -106,6 +106,7 @@ Note: DTD @-annotations are not currently converted to .xsd. For full CLDR file
       <xs:attribute name="author"/>
       <xs:attribute name="layout"/>
       <xs:attribute name="indicator"/>
+      <xs:attribute name="attribution"/>
     </xs:complexType>
   </xs:element>
 
@@ -116,6 +117,8 @@ Note: DTD @-annotations are not currently converted to .xsd. For full CLDR file
 
 
 
+  
+  
   <xs:element name="settings">
     <xs:complexType>
       <xs:attribute name="normalization">