refactor: remove redundant code and over-defensive branches

Consolidate code that existed twice and drop code nothing reaches.

- SSH: hoist the duplicated ASCII hex-nibble decoder out of
  RemoteCharsetConverter and SSHPTYChannel into SSHWireEncoding.hexDigit.
- Transcript: AgentToolDetail.Tint shares BatchTint's vocabulary, so the
  byte-identical detailColor map now delegates to batchColor.
- Commerce: replace ProPaywallState's unreachable default branch and its
  `preconditionFailure("Handled above")` with an exhaustive switch the
  compiler can prove complete.
- Strings: delete the unreferenced Workspace.closePaneAction (the live help
  text uses closePane) and its orphan catalog entry.
- Drop the unused SwiftData and UniformTypeIdentifiers imports.

Co-Authored-By: Claude Code <noreply@anthropic.com>

Frameworks/Resources/Localizable.xcstrings

@@ -7897,29 +7897,6 @@
         }
       }
     },
-    "Close Pane" : {
-      "extractionState" : "manual",
-      "localizations" : {
-        "ja" : {
-          "stringUnit" : {
-            "state" : "translated",
-            "value" : "ペインを閉じる"
-          }
-        },
-        "zh-Hans" : {
-          "stringUnit" : {
-            "state" : "translated",
-            "value" : "关闭窗格"
-          }
-        },
-        "zh-Hant" : {
-          "stringUnit" : {
-            "state" : "translated",
-            "value" : "關閉窗格"
-          }
-        }
-      }
-    },
     "Close Window" : {
       "extractionState" : "manual",
       "localizations" : {

Frameworks/TermindPersistence/TerminalPreferences+Defaults.swift

@@ -1,5 +1,4 @@
 import Foundation
-import SwiftData
 import TermindApplication
 import TermindDomain
 

Frameworks/TermindPresentation/ProPaywallState.swift

@@ -30,22 +30,31 @@ public nonisolated struct ProPaywallState {
             case .expired: state = "expired"
             case .revoked: state = "revoked"
             }
-        default:
+        case .purchased(let ownership):
             canManageSubscription = false
+            isFamilyShared = ownership == .familyShared
             expiresAt = nil
-            if case .purchased(.familyShared) = status {
-                isFamilyShared = true
-            } else {
-                isFamilyShared = false
-            }
-            switch status {
-            case .loading: state = "loading"
-            case .free: state = "free"
-            case .purchased: state = "lifetime"
-            case .verificationFailed: state = "unverified"
-            case .unrestrictedForTesting: state = "development"
-            case .subscription: preconditionFailure("Handled above")
-            }
+            state = "lifetime"
+        case .loading:
+            canManageSubscription = false
+            isFamilyShared = false
+            expiresAt = nil
+            state = "loading"
+        case .free:
+            canManageSubscription = false
+            isFamilyShared = false
+            expiresAt = nil
+            state = "free"
+        case .verificationFailed:
+            canManageSubscription = false
+            isFamilyShared = false
+            expiresAt = nil
+            state = "unverified"
+        case .unrestrictedForTesting:
+            canManageSubscription = false
+            isFamilyShared = false
+            expiresAt = nil
+            state = "development"
         }
     }
 }

Frameworks/TermindPresentation/SingleLineTextInput.swift

@@ -1,6 +1,5 @@
 import Foundation
 import SwiftUI
-import UniformTypeIdentifiers
 
 /// Editing policy for single-line UI fields, not a transformation of stored data or secrets.
 public nonisolated enum SingleLineTextInput {

Frameworks/TermindPresentation/Strings/Workspace.swift

@@ -258,10 +258,6 @@ extension AppStrings {
             "Cancel operation"
         }
 
-        public static var closePaneAction: LocalizedStringResource {
-            "Close Pane"
-        }
-
         public static var closeWindow: LocalizedStringResource {
             "Close Window"
         }

Frameworks/TermindRemoteInfrastructure/SSH/RemoteCharsetConverter.swift

@@ -235,7 +235,8 @@ nonisolated struct RemoteOSC7CharsetFilter: Sendable {
         var index = 0
         while index < bytes.count {
             if bytes[index] == 0x25, index + 2 < bytes.count,
-                let high = hex(bytes[index + 1]), let low = hex(bytes[index + 2])
+                let high = SSHWireEncoding.hexDigit(bytes[index + 1]),
+                let low = SSHWireEncoding.hexDigit(bytes[index + 2])
             {
                 decoded.append(high << 4 | low)
                 index += 3
@@ -271,13 +272,4 @@ nonisolated struct RemoteOSC7CharsetFilter: Sendable {
         }
         return 0
     }
-
-    private func hex(_ byte: UInt8) -> UInt8? {
-        switch byte {
-        case 0x30...0x39: byte - 0x30
-        case 0x41...0x46: byte - 0x41 + 10
-        case 0x61...0x66: byte - 0x61 + 10
-        default: nil
-        }
-    }
 }

Frameworks/TermindRemoteInfrastructure/SSH/SSHPTYChannel.swift

@@ -625,7 +625,8 @@ public nonisolated struct RemoteCommandEventFilter: Sendable {
         var index = 0
         while index < bytes.count {
             if bytes[index] == 0x25, index + 2 < bytes.count,
-                let high = hex(bytes[index + 1]), let low = hex(bytes[index + 2])
+                let high = SSHWireEncoding.hexDigit(bytes[index + 1]),
+                let low = SSHWireEncoding.hexDigit(bytes[index + 2])
             {
                 decoded.append(high << 4 | low)
                 index += 3
@@ -639,15 +640,6 @@ public nonisolated struct RemoteCommandEventFilter: Sendable {
             ?? String(decoding: decodedData, as: UTF8.self)
     }
 
-    private static func hex(_ byte: UInt8) -> UInt8? {
-        switch byte {
-        case 0x30...0x39: byte - 0x30
-        case 0x41...0x46: byte - 0x41 + 10
-        case 0x61...0x66: byte - 0x61 + 10
-        default: nil
-        }
-    }
-
     private static func duration(milliseconds text: Substring) -> TimeInterval? {
         guard let milliseconds = UInt64(text), milliseconds <= 31_536_000_000 else {
             return nil

Frameworks/TermindRemoteInfrastructure/SSH/SSHWireEncoding.swift

@@ -22,4 +22,14 @@ nonisolated enum SSHWireEncoding {
             .replacingOccurrences(of: "=", with: "")
         return "SHA256:\(digest)"
     }
+
+    /// The value of one ASCII hexadecimal digit, or nil for any other byte.
+    static func hexDigit(_ byte: UInt8) -> UInt8? {
+        switch byte {
+        case 0x30...0x39: byte - 0x30
+        case 0x41...0x46: byte - 0x41 + 10
+        case 0x61...0x66: byte - 0x61 + 10
+        default: nil
+        }
+    }
 }

TFM/Features/AI/TranscriptNativeRows.swift

@@ -1602,12 +1602,14 @@ private enum NativeTranscriptFactory {
         }
     }
 
+    /// `AgentToolDetail.Tint` shares `BatchTint`'s vocabulary, so the color
+    /// mapping has one owner.
     private static func detailColor(_ tint: AgentToolDetail.Tint) -> NSColor {
         switch tint {
-        case .secondary: .secondaryLabelColor
-        case .warning: .systemOrange
-        case .success: .systemGreen
-        case .failure: .systemRed
+        case .secondary: batchColor(.secondary)
+        case .warning: batchColor(.warning)
+        case .success: batchColor(.success)
+        case .failure: batchColor(.failure)
         }
     }