Add 2-4 word length preset (closes #475)

Cotabby/Models/OnboardingTemplate.swift

@@ -70,7 +70,7 @@ enum OnboardingTemplate: String, CaseIterable, Identifiable, Equatable, Sendable
     var wordCountPreset: SuggestionWordCountPreset {
         switch self {
         case .quick:
-            return .threeToSeven
+            return .fourToSeven
         case .everyday:
             return .sevenToTwelve
         case .powerful:

Cotabby/Models/SuggestionModels.swift

@@ -12,7 +12,8 @@ import Foundation
 /// User-facing presets that bound how long one inline suggestion may be.
 /// Treating this as an enum keeps the UI and prompt policy in one source of truth.
 enum SuggestionWordCountPreset: String, CaseIterable, Equatable, Hashable, Sendable, Identifiable {
-    case threeToSeven = "3-7"
+    case twoToFour = "2-4"
+    case fourToSeven = "4-7"
     case sevenToTwelve = "7-12"
     case twelveToTwenty = "12-20"
 
@@ -30,8 +31,10 @@ enum SuggestionWordCountPreset: String, CaseIterable, Equatable, Hashable, Senda
 
     var promptInstruction: String {
         switch self {
-        case .threeToSeven:
-            return "Return only the next 3 to 7 words."
+        case .twoToFour:
+            return "Return only the next 2 to 4 words."
+        case .fourToSeven:
+            return "Return only the next 4 to 7 words."
         case .sevenToTwelve:
             return "Return only the next 7 to 12 words."
         case .twelveToTwenty:
@@ -43,10 +46,12 @@ enum SuggestionWordCountPreset: String, CaseIterable, Equatable, Hashable, Senda
     /// word-range cue was removed), so it must track the upper word bound closely. Sized at
     /// ~1.5x the upper word count to leave headroom for multi-token words (contractions, proper
     /// nouns, punctuation) without overrunning the preset. The earlier 50% bump (17/27/45) let
-    /// completions blow past the setting — e.g. ~12 words on the 3-7 preset (#271).
+    /// completions blow past the setting, e.g. ~12 words on the shortest preset (#271).
     var suggestedPredictionTokenBudget: Int {
         switch self {
-        case .threeToSeven:
+        case .twoToFour:
+            return 6
+        case .fourToSeven:
             return 11
         case .sevenToTwelve:
             return 18

Cotabby/Models/SuggestionSettingsModel.swift

@@ -88,6 +88,9 @@ final class SuggestionSettingsModel: ObservableObject {
     private static let ghostTextOpacityDefaultsKey = "cotabbyGhostTextOpacity"
     private static let selectedEngineDefaultsKey = "cotabbySelectedEngine"
     private static let selectedWordCountPresetDefaultsKey = "cotabbySelectedWordCountPreset"
+    /// Pre-#475 raw value for the shortest length tier. Kept here only so the read path can
+    /// rewrite it to `.fourToSeven` on launch; never re-emitted to UserDefaults.
+    private static let legacyShortPresetRawValue = "3-7"
     private static let clipboardContextEnabledDefaultsKey = "cotabbyClipboardContextEnabled"
     private static let fastModeEnabledDefaultsKey = "cotabbyFastModeEnabled"
     private static let performanceTrackingEnabledDefaultsKey = "cotabbyPerformanceTrackingEnabled"
@@ -170,10 +173,17 @@ final class SuggestionSettingsModel: ObservableObject {
             .string(forKey: Self.selectedEngineDefaultsKey)
             .flatMap(SuggestionEngineKind.init(rawValue:))
             ?? .llamaOpenSource
-        let resolvedWordCountPreset = userDefaults
-            .string(forKey: Self.selectedWordCountPresetDefaultsKey)
-            .flatMap(SuggestionWordCountPreset.init(rawValue:))
-            ?? configuration.defaultWordCountPreset
+        let resolvedWordCountPreset: SuggestionWordCountPreset = {
+            let storedRaw = userDefaults.string(forKey: Self.selectedWordCountPresetDefaultsKey)
+            // Migrate the retired "3-7" raw value to its replacement "4-7" so users who picked
+            // the short preset don't silently jump to the default after #475 split the short
+            // tier into 2-4 and 4-7.
+            if storedRaw == Self.legacyShortPresetRawValue {
+                return .fourToSeven
+            }
+            return storedRaw.flatMap(SuggestionWordCountPreset.init(rawValue:))
+                ?? configuration.defaultWordCountPreset
+        }()
         let resolvedClipboardContextEnabled =
             userDefaults.object(forKey: Self.clipboardContextEnabledDefaultsKey) as? Bool ?? false
         // Defaults to false so the visual-context pipeline keeps running for existing users; opting

CotabbyTests/ModelAndPresentationValueTests.swift

@@ -39,8 +39,11 @@ final class SuggestionTextColorCodecTests: XCTestCase {
 
 final class SuggestionModelValueTests: XCTestCase {
     func test_wordCountPresetsExposeMatchingPromptInstructionsAndTokenBudgets() {
-        XCTAssertEqual(SuggestionWordCountPreset.threeToSeven.promptInstruction, "Return only the next 3 to 7 words.")
-        XCTAssertEqual(SuggestionWordCountPreset.threeToSeven.suggestedPredictionTokenBudget, 11)
+        XCTAssertEqual(SuggestionWordCountPreset.twoToFour.promptInstruction, "Return only the next 2 to 4 words.")
+        XCTAssertEqual(SuggestionWordCountPreset.twoToFour.suggestedPredictionTokenBudget, 6)
+
+        XCTAssertEqual(SuggestionWordCountPreset.fourToSeven.promptInstruction, "Return only the next 4 to 7 words.")
+        XCTAssertEqual(SuggestionWordCountPreset.fourToSeven.suggestedPredictionTokenBudget, 11)
 
         XCTAssertEqual(SuggestionWordCountPreset.sevenToTwelve.promptInstruction, "Return only the next 7 to 12 words.")
         XCTAssertEqual(SuggestionWordCountPreset.sevenToTwelve.suggestedPredictionTokenBudget, 18)

CotabbyTests/OnboardingTemplateRecommenderTests.swift

@@ -26,7 +26,7 @@ final class OnboardingTemplateRecommenderTests: XCTestCase {
 
     func testAppleIntelligenceStillCarriesTierBehaviorFlags() {
         let quick = OnboardingTemplateRecommender.resolvePlan(for: .quick, engine: .appleIntelligence)
-        XCTAssertEqual(quick.wordCountPreset, .threeToSeven)
+        XCTAssertEqual(quick.wordCountPreset, .fourToSeven)
         XCTAssertTrue(quick.enablesFastMode)
         XCTAssertFalse(quick.enablesMultiLine)
         XCTAssertFalse(quick.enablesClipboardContext)