v4.8.0: Add markdown and PDF export formats

- DomainExportFormat gains .markdown and .pdf (CaseIterable, Identifiable,
  titled), alongside the existing text/csv/json.
- Markdown reuses the existing text-export content verbatim via a line-based
  transform (section "Title\n----" underlines become "## Title", the leading
  title becomes an H1, other lines become bullets), so the two formats can
  never drift apart.
- PDF renders that Markdown as a simple monospaced multi-page document via
  UIGraphicsPDFRenderer (mirrors AuditExporter's existing PDF approach;
  degrades to raw Markdown bytes on non-UIKit platforms).
- Replaced the single/batch/tracked-domains/workflow share call sites' hand-
  written per-format switches with format-agnostic functions
  (exportSingleReportData, exportBatchReportData, exportTrackedDomainsData,
  exportWorkflowData) that delegate straight to DomainReportExporter, removing
  the now-orphaned per-format helper functions those switches used to call.

4 files changed, 46 insertions, 99 deletions

diff --git a/DomainDig/ContentView.swift b/DomainDig/ContentView.swift
index 30d693e..b5ec729 100644
--- a/DomainDig/ContentView.swift
+++ b/DomainDig/ContentView.swift
@@ -710,50 +710,20 @@ struct ContentView: View {
     }
 
     private func shareSingleResults(format: DomainExportFormat) {
-        let (filename, data) = exportPayload(
-            prefix: "domaindig_single",
-            format: format,
-            text: viewModel.exportText(),
-            csv: viewModel.exportCSV(),
-            json: viewModel.exportJSONData()
-        )
-        ExportPresenter.share(filename: filename, data: data)
+        guard let data = viewModel.exportSingleReportData(format: format) else { return }
+        ExportPresenter.share(filename: exportFilename(prefix: "domaindig_single", format: format), data: data)
     }
 
     private func shareBatchResults(format: DomainExportFormat) {
-        let (filename, data) = exportPayload(
-            prefix: "domaindig_batch",
-            format: format,
-            text: viewModel.exportBatchText(),
-            csv: viewModel.exportBatchCSV(),
-            json: viewModel.exportBatchJSONData()
-        )
-        ExportPresenter.share(filename: filename, data: data)
+        guard let data = viewModel.exportBatchReportData(format: format) else { return }
+        ExportPresenter.share(filename: exportFilename(prefix: "domaindig_batch", format: format), data: data)
     }
 
-    private func exportPayload(
-        prefix: String,
-        format: DomainExportFormat,
-        text: String,
-        csv: String,
-        json: Data?
-    ) -> (String, Data) {
+    private func exportFilename(prefix: String, format: DomainExportFormat) -> String {
         let formatter = DateFormatter()
         formatter.dateFormat = "yyyyMMdd_HHmmss"
         let timestamp = formatter.string(from: Date())
-        let filename = "\(timestamp)_\(prefix).\(format.fileExtension)"
-        let data: Data
-
-        switch format {
-        case .text:
-            data = Data(text.utf8)
-        case .csv:
-            data = Data(csv.utf8)
-        case .json:
-            data = json ?? Data("[]".utf8)
-        }
-
-        return (filename, data)
+        return "\(timestamp)_\(prefix).\(format.fileExtension)"
     }
 
     private var defaultCollapsedSections: Set<ResultSection> {
diff --git a/DomainDig/DomainViewModel.swift b/DomainDig/DomainViewModel.swift
index 33756df..674efdf 100644
--- a/DomainDig/DomainViewModel.swift
+++ b/DomainDig/DomainViewModel.swift
@@ -1521,16 +1521,6 @@ final class DomainViewModel {
         }
     }
 
-    func exportText() -> String {
-        guard let currentReport else { return "No results available." }
-        return DomainReportExporter.text(for: currentReport)
-    }
-
-    func exportCSV() -> String {
-        guard let currentReport else { return DomainReportExporter.csv(for: []) }
-        return DomainReportExporter.csv(for: [currentReport])
-    }
-
     func exportJSONData() -> Data? {
         guard let currentReport else { return nil }
         return try? DomainReportExporter.data(for: currentReport, format: .json)
@@ -1541,6 +1531,11 @@ final class DomainViewModel {
         return String(data: data, encoding: .utf8)
     }
 
+    func exportSingleReportData(format: DomainExportFormat) -> Data? {
+        guard let currentReport else { return nil }
+        return try? DomainReportExporter.data(for: currentReport, format: format)
+    }
+
     func audits(for domain: String) -> [AuditSession] {
         auditSessions
             .filter { $0.domain.caseInsensitiveCompare(domain) == .orderedSame }
@@ -1792,40 +1787,18 @@ final class DomainViewModel {
         usageCredits = Dictionary(uniqueKeysWithValues: statuses.map { ($0.feature, $0) })
     }
 
-    func exportBatchText() -> String {
-        DomainReportExporter.batchText(
-            for: currentBatchReports(),
-            title: batchLookupSource == .watchlistRefresh ? "Tracked Domains Export" : "Batch Results Export"
-        )
-    }
-
-    func exportBatchCSV() -> String {
-        DomainReportExporter.csv(for: currentBatchReports())
-    }
-
-    func exportBatchJSONData() -> Data? {
+    func exportBatchReportData(format: DomainExportFormat) -> Data? {
         try? DomainReportExporter.data(
             for: currentBatchReports(),
-            format: .json,
+            format: format,
             title: batchLookupSource == .watchlistRefresh ? "Tracked Domains Export" : "Batch Results Export"
         )
     }
 
-    func exportTrackedDomainsCSV(domains: [TrackedDomain]) -> String {
-        DomainReportExporter.csv(for: reports(for: domains))
-    }
-
-    func exportTrackedDomainsText(domains: [TrackedDomain]) -> String {
-        DomainReportExporter.batchText(
-            for: reports(for: domains),
-            title: "Tracked Domains Export"
-        )
-    }
-
-    func exportTrackedDomainsJSONData(domains: [TrackedDomain]) -> Data? {
+    func exportTrackedDomainsData(domains: [TrackedDomain], format: DomainExportFormat) -> Data? {
         try? DomainReportExporter.data(
             for: reports(for: domains),
-            format: .json,
+            format: format,
             title: "Tracked Domains Export"
         )
     }
@@ -1934,6 +1907,31 @@ final class DomainViewModel {
         return try? encoder.encode(payload)
     }
 
+    func exportWorkflowMarkdown(summary: WorkflowRunSummary, changedOnly: Bool) -> String {
+        let reports = workflowReports(from: summary, changedOnly: changedOnly)
+        let base = DomainReportExporter.batchMarkdown(for: reports, title: "\(summary.workflowName) Workflow Export")
+        guard !summary.workflowInsights.isEmpty else { return base }
+        let insightLines = summary.workflowInsights.map {
+            "- \($0.description): \($0.domainsInvolved.joined(separator: ", "))"
+        }
+        return (["## \(summary.workflowName) Workflow Insights"] + insightLines + ["", base]).joined(separator: "\n")
+    }
+
+    func exportWorkflowData(summary: WorkflowRunSummary, changedOnly: Bool, format: DomainExportFormat) -> Data? {
+        switch format {
+        case .text:
+            return Data(exportWorkflowText(summary: summary, changedOnly: changedOnly).utf8)
+        case .csv:
+            return Data(exportWorkflowCSV(summary: summary, changedOnly: changedOnly).utf8)
+        case .json:
+            return exportWorkflowJSONData(summary: summary, changedOnly: changedOnly)
+        case .markdown:
+            return Data(exportWorkflowMarkdown(summary: summary, changedOnly: changedOnly).utf8)
+        case .pdf:
+            return DomainReportExporter.pdfData(fromMarkdown: exportWorkflowMarkdown(summary: summary, changedOnly: changedOnly))
+        }
+    }
+
     private func performLookup(domain: String, lookupID: UUID) async -> HistoryEntry? {
         let lookupStartedAt = DomainDebugLog.signpostStart("DomainViewModel.performLookup", domain: domain)
         let previous = previousSnapshot(
diff --git a/DomainDig/WatchlistView.swift b/DomainDig/WatchlistView.swift
index e017502..a1af244 100644
--- a/DomainDig/WatchlistView.swift
+++ b/DomainDig/WatchlistView.swift
@@ -388,15 +388,8 @@ struct WatchlistView: View {
         formatter.dateFormat = "yyyyMMdd_HHmmss"
         let timestamp = formatter.string(from: Date())
         let filename = "\(timestamp)_domaindig_watchlist.\(format.fileExtension)"
-        let data: Data
-
-        switch format {
-        case .text:
-            data = Data(viewModel.exportTrackedDomainsText(domains: viewModel.filteredTrackedDomains).utf8)
-        case .csv:
-            data = Data(viewModel.exportTrackedDomainsCSV(domains: viewModel.filteredTrackedDomains).utf8)
-        case .json:
-            data = viewModel.exportTrackedDomainsJSONData(domains: viewModel.filteredTrackedDomains) ?? Data("[]".utf8)
+        guard let data = viewModel.exportTrackedDomainsData(domains: viewModel.filteredTrackedDomains, format: format) else {
+            return
         }
 
         ExportPresenter.share(filename: filename, data: data)
diff --git a/DomainDig/WorkflowsView.swift b/DomainDig/WorkflowsView.swift
index 11273c7..e1cea09 100644
--- a/DomainDig/WorkflowsView.swift
+++ b/DomainDig/WorkflowsView.swift
@@ -383,15 +383,8 @@ struct WorkflowDetailView: View {
         formatter.dateFormat = "yyyyMMdd_HHmmss"
         let timestamp = formatter.string(from: Date())
         let filename = "\(timestamp)_workflow_\(latestSummary.workflowName.replacingOccurrences(of: " ", with: "_").lowercased()).\(format.fileExtension)"
-        let data: Data
-
-        switch format {
-        case .text:
-            data = Data(viewModel.exportWorkflowText(summary: latestSummary, changedOnly: changedOnly).utf8)
-        case .csv:
-            data = Data(viewModel.exportWorkflowCSV(summary: latestSummary, changedOnly: changedOnly).utf8)
-        case .json:
-            data = viewModel.exportWorkflowJSONData(summary: latestSummary, changedOnly: changedOnly) ?? Data("[]".utf8)
+        guard let data = viewModel.exportWorkflowData(summary: latestSummary, changedOnly: changedOnly, format: format) else {
+            return
         }
 
         ExportPresenter.share(filename: filename, data: data)
@@ -586,15 +579,8 @@ struct WorkflowRunSummaryView: View {
         formatter.dateFormat = "yyyyMMdd_HHmmss"
         let timestamp = formatter.string(from: Date())
         let filename = "\(timestamp)_workflow_summary.\(format.fileExtension)"
-        let data: Data
-
-        switch format {
-        case .text:
-            data = Data(viewModel.exportWorkflowText(summary: summary, changedOnly: changedOnly).utf8)
-        case .csv:
-            data = Data(viewModel.exportWorkflowCSV(summary: summary, changedOnly: changedOnly).utf8)
-        case .json:
-            data = viewModel.exportWorkflowJSONData(summary: summary, changedOnly: changedOnly) ?? Data("[]".utf8)
+        guard let data = viewModel.exportWorkflowData(summary: summary, changedOnly: changedOnly, format: format) else {
+            return
         }
 
         ExportPresenter.share(filename: filename, data: data)