feat: add configurable multi-threaded parallel scanning for library tasks

JellyfinPlugin/Configuration/configPage.html

@@ -33,6 +33,12 @@
                         <div class="fieldDescription">Choose how the plugin should remove black bars. Auto mode uses lightweight CSS clipping for Web browser DirectPlay, and falls back to FFmpeg transcoding for native apps or unsupported video formats.</div>
                     </div>
 
+                    <div class="inputContainer">
+                        <label class="inputLabel inputLabelUnfocused" for="txtMaxParallelScans">Max Parallel Scans (1 - 16):</label>
+                        <input type="number" step="1" min="1" max="16" id="txtMaxParallelScans" is="emby-input" required />
+                        <div class="fieldDescription">Number of files to analyze concurrently during library scheduled tasks. Default is 4. Higher values speed up library scans on multi-core CPUs.</div>
+                    </div>
+
                     <div>
                         <button is="emby-button" type="submit" class="raised button-submit block emby-button">
                             <span>Save</span>
@@ -56,6 +62,7 @@
                     var mode = config.PlaybackMode || "Auto";
                     if (mode === "Both") mode = "Auto";
                     $('#selectPlaybackMode', page).val(mode);
+                    $('#txtMaxParallelScans', page).val(config.MaxParallelScans || 4);
                     Dashboard.hideLoadingMsg();
                 });
             });
@@ -69,6 +76,7 @@
                     config.IsEnabled = $('#chkEnablePlugin', form).prop('checked');
                     config.CropDetectLimit = parseFloat($('#txtCropLimit', form).val());
                     config.PlaybackMode = $('#selectPlaybackMode', form).val();
+                    config.MaxParallelScans = parseInt($('#txtMaxParallelScans', form).val(), 10) || 4;
                     
                     ApiClient.updatePluginConfiguration(BlackBarRemoverConfig.pluginUniqueId, config).then(function (result) {
                         Dashboard.processPluginConfigurationUpdateResult(result);