Nucleic: Collapseable session transcript blocks

NucleicRemote/NucleicRemote/Views/Transcript/ToolGroupRow.swift

@@ -20,11 +20,7 @@ struct ToolCallCard: View {
             // Folded lock-lifecycle lines read as part of the edit card (always visible, not gated
             // by expand), so the lock brackets its edit rather than sorting after it — as on the Mac.
             if !group.lockLines.isEmpty {
-                VStack(alignment: .leading, spacing: 2) {
+                LockLinesSection(locks: group.lockLines)
-                    ForEach(Array(group.lockLines.enumerated()), id: \.offset) { _, lock in
-                        LockLineRow(lock: lock)
-                    }
-                }
             }
             if expanded { details }
         }
@@ -570,6 +566,99 @@ struct LockLineRow: View {
     }
 }
 
+/// The whole lock trail folded onto one tool card — the phone echo of the Mac's
+/// `LockLinesSection`. A short trail (an ordinary edit's waiting → acquired → released) stays
+/// literal; a long one — a supervising turn holding the lock for every file its workers touch —
+/// collapses to one summary line that expands into a `LockDigest`: one entry per path at its
+/// latest state, grouped under its directory so a shared prefix is written once.
+struct LockLinesSection: View {
+    let locks: [NoteLock]
+    /// Trails at or below this many events render as plain lines (the common edit card).
+    static let inlineLimit = 4
+    @State private var expanded = false
+
+    var body: some View {
+        if locks.count <= Self.inlineLimit {
+            VStack(alignment: .leading, spacing: 2) {
+                ForEach(Array(locks.enumerated()), id: \.offset) { _, lock in
+                    LockLineRow(lock: lock)
+                }
+            }
+        } else {
+            let digest = LockDigest(locks)
+            VStack(alignment: .leading, spacing: 5) {
+                Button {
+                    withAnimation(.easeInOut(duration: 0.15)) { expanded.toggle() }
+                } label: { summary(digest) }
+                    .buttonStyle(.plain)
+                if expanded { LockDigestBody(digest: digest) }
+            }
+        }
+    }
+
+    private func summary(_ digest: LockDigest) -> some View {
+        HStack(alignment: .firstTextBaseline, spacing: 6) {
+            Image(systemName: LockLineStyle.icon(digest.dominantState))
+                .font(.caption2).foregroundStyle(.tertiary).frame(width: 15)
+            Text(digest.headline)
+                .font(.caption).foregroundStyle(.secondary)
+            Image(systemName: expanded ? "chevron.down" : "chevron.right")
+                .font(.system(size: 8, weight: .semibold)).foregroundStyle(.tertiary)
+            Spacer(minLength: 0)
+        }
+        .contentShape(Rectangle())
+    }
+}
+
+/// The expanded lock digest: a block per state, and within it one line per directory carrying
+/// that directory's basenames. A directory holding a single file collapses back to its full path.
+private struct LockDigestBody: View {
+    let digest: LockDigest
+
+    var body: some View {
+        let sections = digest.sections
+        VStack(alignment: .leading, spacing: 6) {
+            ForEach(sections, id: \.state) { section in
+                VStack(alignment: .leading, spacing: 3) {
+                    // With one state the summary line above already names it; only a mixed
+                    // trail needs each block labelled.
+                    if sections.count > 1 {
+                        HStack(spacing: 5) {
+                            Image(systemName: LockLineStyle.icon(section.state))
+                                .font(.system(size: 9)).foregroundStyle(.tertiary)
+                            Text("\(LockDigest.sectionTitle(section.state)) · \(section.count)")
+                                .font(.caption2.weight(.medium)).foregroundStyle(.secondary)
+                        }
+                    }
+                    ForEach(section.directories, id: \.directory) { directory in
+                        group(directory)
+                    }
+                }
+            }
+        }
+        .padding(.leading, 21)
+    }
+
+    @ViewBuilder
+    private func group(_ directory: LockDigest.Directory) -> some View {
+        if let path = directory.singlePath {
+            Text(path)
+                .font(.caption2.monospaced()).foregroundStyle(.secondary)
+                .lineLimit(1).truncationMode(.middle)
+        } else {
+            VStack(alignment: .leading, spacing: 1) {
+                Text(directory.directory.isEmpty ? "./" : "\(directory.directory)/")
+                    .font(.caption2.monospaced()).foregroundStyle(.tertiary)
+                    .lineLimit(1).truncationMode(.middle)
+                Text(directory.files.joined(separator: ", "))
+                    .font(.caption2).foregroundStyle(.secondary)
+                    .fixedSize(horizontal: false, vertical: true)
+                    .padding(.leading, 10)
+            }
+        }
+    }
+}
+
 /// SF Symbols for the common tools + file-change kinds, so a glance reads the action.
 enum ToolGlyph {
     static func icon(_ name: String) -> String {