Psych, switch "default" to "active", add justification

DECISIONS.md

@@ -49,3 +49,18 @@ Uninstallation is not provided yet. I had this partially implemented (one attemp
 - [erikberglund/SwiftPrivilegedHelper](https://github.com/erikberglund/SwiftPrivilegedHelper)
 - [aronskaya/smjobbless](https://github.com/aronskaya/smjobbless)
 - [securing/SimpleXPCApp](https://github.com/securing/SimpleXPCApp)
+
+## Selecting the active version of Xcode
+
+This isn't a technical decision, but we spent enough time talking about this that it's probably worth sharing. When a user has more than one version of Xcode installed, a specific version of the developer tools can be selected with the `xcode-select` tool. The selected version of tools like xcodebuild or xcrun will be used unless the DEVELOPER_DIR environment variable has been set to a different path. You can read more about this in the `xcode-select` man pages. Notably, the man pages and [some notarization documentation](https://developer.apple.com/documentation/xcode/notarizing_macos_software_before_distribution) use the term "active" to indicate the Xcode version that's been selected. [This](https://developer.apple.com/library/archive/technotes/tn2339/_index.html#//apple_ref/doc/uid/DTS40014588-CH1-HOW_DO_I_SELECT_THE_DEFAULT_VERSION_OF_XCODE_TO_USE_FOR_MY_COMMAND_LINE_TOOLS_) older tech note uses the term "default". And of course, the `xcode-select` tool has the term "select" in its name. xcodes used the terms "select" and "selected" for this functionality, intending to match the xcode-select tool.
+
+Here are the descriptions of these terms from [Apple's Style Guide](https://books.apple.com/ca/book/apple-style-guide/id1161855204):
+
+> active: Use to refer to the app or window currently being used. Preferred to in front.
+> default: OK to use to describe the state of settings before the user changes them. See also preset
+> preset: Use to refer to a group of customized settings an app provides or the user saves for reuse.
+> select: Use select, not choose, to refer to the action users perform when they select among multiple objects
+
+Xcodes.app has this same functionality as xcodes, which still uses `xcode-select` under the hood, but because the main UI is a list of selectable rows, there _may_ be some ambiguity about the meaning of "selected". "Default" has a less clear connection to `xcode-select`'s name, but does accurately describe the behaviour that results. In Xcode 11 Launch Services also uses the selected Xcode version when opening a (GUI) developer tool bundled with Xcode, like Instruments. We could also try to follow Apple's lead by using the term "active" from the `xcode-select` man pages and notarization documentation. According to the style guide "active" already has a clear meaning in a GUI context.
+
+Ultimately, we've decided to align with Apple's usage of "active" and "make active" in this specific context, despite possible confusion with the definition in the style guide. 

Xcodes/Backend/XcodeCommands.swift

@@ -58,7 +58,11 @@ struct SelectButton: View {
     
     var body: some View {
         Button(action: select) {
-            Text("Select")
+            if xcode?.selected == true {
+                Text("Active")
+            } else {
+                Text("Make active")
+            }
         }
         .disabled(xcode?.selected != false)
         .help("Select")

Xcodes/Frontend/XcodeList/XcodeListViewRow.swift

@@ -22,6 +22,7 @@ struct XcodeListViewRow: View {
             Spacer()
             
             selectControl(for: xcode)
+                .padding(.trailing, 16)
             installControl(for: xcode)
         }
         .contextMenu {
@@ -51,25 +52,34 @@ struct XcodeListViewRow: View {
     
     @ViewBuilder
     private func selectControl(for xcode: Xcode) -> some View {
-        if xcode.selected {
-            Image(systemName: "checkmark.circle.fill")
-                .foregroundColor(.green)
-                .help("This version is selected as the default")
+        if xcode.installed {
+            if xcode.selected {
+                Image(systemName: "checkmark.circle.fill")
+                    .foregroundColor(.green)
+                    .help("This is the active version")
+            } else {
+                Button(action: { appState.select(id: xcode.id) }) {
+                    Image(systemName: "checkmark.circle")
+                        .foregroundColor(.secondary)
+                }
+                .buttonStyle(PlainButtonStyle())
+                .help("Make this the active version")
+            }
+        } else {
+            EmptyView()
         }
     }
     
     @ViewBuilder
     private func installControl(for xcode: Xcode) -> some View {
-        if xcode.selected {
-            Button("DEFAULT") { appState.select(id: xcode.id) }
-                .buttonStyle(AppStoreButtonStyle(primary: false, highlighted: selected))
-                .disabled(true)
-        } else if xcode.installed {
-            Button("SELECT") { appState.select(id: xcode.id) }
-                .buttonStyle(AppStoreButtonStyle(primary: false, highlighted: selected))
+        if xcode.installed {
+            Button("OPEN") { appState.open(id: xcode.id) }
+                .buttonStyle(AppStoreButtonStyle(primary: true, highlighted: selected))
+                .help("Open this version")
         } else {
             Button("INSTALL") { print("Installing...") }
-                .buttonStyle(AppStoreButtonStyle(primary: true, highlighted: selected))   
+                .buttonStyle(AppStoreButtonStyle(primary: false, highlighted: selected))
+                .help("Install this version")
         }
     }
 }