Avoid escaping slashes in JSON output (#2205)

Fixes #2204.

Swift's default JSONEncoder output escapes forward slashes, which makes CLI JSON paths and URLs harder to read and copy. This change makes the shared CLI JSON renderer always use .withoutEscapingSlashes and routes machine list --format json through that renderer while preserving its ISO-8601 date encoding.

OpenAI Codex assisted with investigation, implementation, and verification. The final change is limited to JSON rendering behavior and focused regression coverage.

Co-authored-by: taljeon <169621860+taljeon@users.noreply.github.com>

Sources/ContainerCommands/Machine/MachineList.swift

@@ -61,10 +61,8 @@ extension Application {
                 let printables = machines.map {
                     PrintableMachine($0, isDefault: $0.id == defaultMachine)
                 }
-                let encoder = JSONEncoder()
-                encoder.dateEncodingStrategy = .iso8601
-                let data = try encoder.encode(printables)
-                print(String(decoding: data, as: UTF8.self))
+                let options = JSONOptions(dateEncodingStrategy: .iso8601)
+                try Output.emit(Output.renderJSON(printables, options: options))
                 return
             }
 

Sources/ContainerCommands/OutputRendering.swift

@@ -44,7 +44,7 @@ public enum Output {
     /// Renders an `Encodable` value as a JSON string.
     public static func renderJSON<T: Encodable>(_ value: T, options: JSONOptions = .compact) throws -> String {
         let encoder = JSONEncoder()
-        encoder.outputFormatting = options.outputFormatting
+        encoder.outputFormatting = options.outputFormatting.union(.withoutEscapingSlashes)
         encoder.dateEncodingStrategy = options.dateEncodingStrategy
         let data = try encoder.encode(value)
         return String(decoding: data, as: UTF8.self)

Tests/ContainerCommandsTests/ListFormattingTests.swift

@@ -163,6 +163,15 @@ struct RenderJSONTests {
         #expect(!json.contains("\n"))
     }
 
+    @Test
+    func doesNotEscapeSlashes() throws {
+        let item = TestItem(id: "/foo/bar", name: "https://example.com/path")
+        let json = try Output.renderJSON(item)
+        #expect(json.contains("/foo/bar"))
+        #expect(json.contains("https://example.com/path"))
+        #expect(!json.contains("\\/"))
+    }
+
     @Test
     func prettyIsMultiLine() throws {
         let items = [TestItem(id: "a", name: "b")]