Cmdpal: Peek command in indexer (#44581)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
Add a peek command, so we could quickly view the files found by indexer

I’m aware that wiring the Peek command directly into the indexer
extension is fairly PowerToys-specific.
I’m open to suggestions if we think this should instead be handled via a
more general extension / plugin mechanism; if a broader framework is
planned, I’m happy to wait and revisit this once that structure is in
place.

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## PR Checklist

- [ ] Closes: #43517
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issues) -->
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
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- [ ] **Documentation updated:** If checked, please file a pull request
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repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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## Detailed Description of the Pull Request / Additional comments

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src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Properties/Resources.Designer.cs

@@ -132,6 +132,33 @@ namespace Microsoft.CmdPal.Ext.Indexer.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Peek preview.
+        /// </summary>
+        internal static string Indexer_Command_Peek {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Failed to launch Peek.
+        /// </summary>
+        internal static string Indexer_Command_Peek_Failed {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek_Failed", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to PowerToys Peek is not available.
+        /// </summary>
+        internal static string Indexer_Command_Peek_NotAvailable {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek_NotAvailable", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Search all files.
         /// </summary>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Properties/Resources.resx

@@ -202,4 +202,13 @@ You can try searching all files on this PC or adjust your indexing settings.</va
   <data name="Indexer_Filter_Files_Only" xml:space="preserve">
     <value>Files</value>
   </data>
+  <data name="Indexer_Command_Peek" xml:space="preserve">
+    <value>Peek preview</value>
+  </data>
+  <data name="Indexer_Command_Peek_NotAvailable" xml:space="preserve">
+    <value>PowerToys Peek is not available</value>
+  </data>
+  <data name="Indexer_Command_Peek_Failed" xml:space="preserve">
+    <value>Failed to launch Peek</value>
+  </data>
 </root>