refactor(webui): remove pipeline viewer feature

Remove the read-only pipeline viewer from the web UI:
- Delete PipelineViewer.razor page and supporting components
- Delete PipelineController and PipelineMapper from API
- Delete Pipeline DTOs from Core
- Delete PipelineApiClient from Client
- Remove navigation link and DI registrations
- Delete obsolete plan documents

The ConfigManager utility retains pipeline editing capabilities.

NEW/src/JdeScoping.Core/Models/Pipelines/PipelineConfigDto.cs

@@ -1,51 +0,0 @@
-namespace JdeScoping.Core.Models.Pipelines;
-
-/// <summary>
-/// Pipeline configuration DTO for display.
-/// </summary>
-public record PipelineConfigDto(
-    string Name,
-    PipelineSourceDto Source,
-    PipelineDestinationDto Destination,
-    PipelineSchedulesDto Schedules,
-    int PreScriptCount,
-    int PostScriptCount,
-    List<string>? PreScripts,
-    List<string>? PostScripts);
-
-public record PipelineSourceDto(
-    string Connection,
-    string? QueryPreview,
-    string? MassQueryPreview,
-    string? Query,
-    string? MassQuery,
-    List<PipelineParameterDto> Parameters);
-
-public record PipelineParameterDto(
-    string Name,
-    string? Format,
-    string Source);
-
-public record PipelineDestinationDto(
-    string Table,
-    string OperationType,
-    List<string>? MatchColumns,
-    List<string>? ExcludeFromUpdate);
-
-public record PipelineSchedulesDto(
-    PipelineScheduleDto Mass,
-    PipelineScheduleDto Daily,
-    PipelineScheduleDto Hourly);
-
-public record PipelineScheduleDto(
-    bool Enabled,
-    int IntervalMinutes,
-    bool PrePurge,
-    bool ReIndex,
-    bool IntervalIsOverride,
-    bool PrePurgeIsOverride,
-    bool ReIndexIsOverride,
-    string? Query,
-    List<PipelineParameterDto> Parameters,
-    List<string>? PreScripts,
-    List<string>? PostScripts);

NEW/src/JdeScoping.Core/Models/Pipelines/PipelineExecutionDto.cs

@@ -1,16 +0,0 @@
-namespace JdeScoping.Core.Models.Pipelines;
-
-using JdeScoping.Core.Models.Enums;
-
-/// <summary>
-/// Pipeline execution history.
-/// </summary>
-public record PipelineExecutionsResponse(List<PipelineExecutionDto> Executions);
-
-public record PipelineExecutionDto(
-    UpdateTypes ScheduleType,
-    DateTime StartTime,
-    DateTime? EndTime,
-    TimeSpan? Duration,
-    long RecordCount,
-    bool WasSuccessful);

NEW/src/JdeScoping.Core/Models/Pipelines/PipelineListResponse.cs

@@ -1,6 +0,0 @@
-namespace JdeScoping.Core.Models.Pipelines;
-
-/// <summary>
-/// Response containing list of available pipeline names.
-/// </summary>
-public record PipelineListResponse(List<string> PipelineNames);

NEW/src/JdeScoping.Core/Models/Pipelines/PipelineStatusDto.cs

@@ -1,17 +0,0 @@
-namespace JdeScoping.Core.Models.Pipelines;
-
-using JdeScoping.Core.Models.Enums;
-
-/// <summary>
-/// Pipeline schedule status for each update type.
-/// </summary>
-public record PipelineStatusResponse(List<PipelineScheduleStatusDto> Statuses);
-
-public record PipelineScheduleStatusDto(
-    UpdateTypes ScheduleType,
-    DateTime? LastRun,
-    bool LastRunWasSuccessful,
-    DateTime? LastSuccessfulRun,
-    DateTime? NextRequiredRun,
-    bool IsOverdue,
-    int IntervalMinutes);