fix(polish): gate test-build style generation at 1,250 chars and cap export at 5,000

Remove the test-mode unlimited personal-style corpus bypass and replace it with a real 1,250-character minimum gate. Production stays at 2,500. Training-corpus export and the diagnostics view now use a 5,000-character upper bound so the user's full private history never leaves the device in a single export.

- Add PolishStyleLearningCorpusBuilder.testBuildEffectiveCharacterCount (1,250) and trainingExtractionMaximumCharacterCount (5,000); trainingWindow(from:maximumCharacterCount:) accepts a custom cap.
- PolishStylesView: drop bypassesStyleLearningCharacterGate in favor of styleLearningMinimumCharacterCount, unify the ready/remaining text, remove the obsolete polishStyles.learn.testBuildReady key.
- PolishStyleCorpusExportStore: pass the 5,000 cap to trainingWindow and expose trainingExtractionMaximumCharacterCount in the export schema.
- FlowDiagnosticsSettingsView: show the export-sized (5,000-cap) corpus so the diagnostics match what the export ZIP actually contains.
- Tests: rewrite the export cap test for 5,000, add below-cap coverage, add trainingWindow(maximumCharacterCount:) unit coverage, and convert the old UI test into a regression test for the 1,250 test-build minimum.
- L10n: drop the testBuildReady string in en + zh-Hans, update diagnostics.corpus.ready to mention 5,000.
- CHANGELOG: bilingual entry under [Unreleased].

OSGKeyboard/Services/PolishStyleCorpusExportStore.swift

@@ -15,6 +15,10 @@ struct PolishStyleCorpusExport: Codable, Equatable {
     let appBuild: String
     let effectiveCharacterCount: Int
     let requiredEffectiveCharacterCount: Int
+    /// Maximum effective characters included in this export. Caps the
+    /// training-corpus window even when the user has accumulated far
+    /// more history than the production 2,500-character unlock gate.
+    let trainingExtractionMaximumCharacterCount: Int
     let examples: [Example]
 
     struct Example: Codable, Equatable {
@@ -55,7 +59,10 @@ final class PolishStyleCorpusExportStore {
         let eligibleCorpus = PolishStyleLearningCorpusBuilder.build(from: history)
         guard !eligibleCorpus.examples.isEmpty else { return nil }
         let corpus = PolishStyleLearningCorpusBuilder.trainingWindow(
-            from: eligibleCorpus.examples
+            from: eligibleCorpus.examples,
+            maximumCharacterCount:
+                PolishStyleLearningCorpusBuilder
+                    .trainingExtractionMaximumCharacterCount
         )
 
         let examples = corpus.examples
@@ -77,6 +84,9 @@ final class PolishStyleCorpusExportStore {
             effectiveCharacterCount: corpus.effectiveCharacterCount,
             requiredEffectiveCharacterCount:
                 PolishStyleLearningCorpusBuilder.requiredEffectiveCharacterCount,
+            trainingExtractionMaximumCharacterCount:
+                PolishStyleLearningCorpusBuilder
+                    .trainingExtractionMaximumCharacterCount,
             examples: examples
         )
     }

OSGKeyboard/Views/FlowDiagnosticsSettingsView.swift

@@ -135,7 +135,10 @@ struct FlowDiagnosticsSettingsView: View {
             from: historyStore.snapshot()
         )
         return PolishStyleLearningCorpusBuilder.trainingWindow(
-            from: eligibleCorpus.examples
+            from: eligibleCorpus.examples,
+            maximumCharacterCount:
+                PolishStyleLearningCorpusBuilder
+                    .trainingExtractionMaximumCharacterCount
         )
     }
 

OSGKeyboard/Views/PolishStylesView.swift

@@ -55,7 +55,8 @@ struct PolishStylesView: View {
                     outputLanguage: language,
                     minimumEffectiveCharacterCount:
                         AppDistributionChannel.allowsInternalTools
-                            ? 0
+                            ? PolishStyleLearningCorpusBuilder
+                                .testBuildEffectiveCharacterCount
                             : PolishStyleLearningCorpusBuilder
                                 .requiredEffectiveCharacterCount
                 )
@@ -158,17 +159,20 @@ struct PolishStylesView: View {
         PolishStyleLearningCorpusBuilder.build(from: history.snapshot())
     }
 
-    /// Debug and TestFlight builds may exercise the complete generation
-    /// pipeline before enough personal corpus exists. App Store builds keep
-    /// the production 2,500-character gate.
-    private var bypassesStyleLearningCharacterGate: Bool {
+    /// Minimum effective character count required to unlock personal style
+    /// generation. Debug + TestFlight builds use a lower 1,250-character
+    /// gate so internal testers can still exercise the pipeline; the
+    /// previous 0 / "unlimited" bypass has been removed.
+    private var styleLearningMinimumCharacterCount: Int {
         AppDistributionChannel.allowsInternalTools
+            ? PolishStyleLearningCorpusBuilder.testBuildEffectiveCharacterCount
+            : PolishStyleLearningCorpusBuilder.requiredEffectiveCharacterCount
     }
 
     private func isEligibleForStyleGeneration(
         _ corpus: PolishStyleLearningCorpus
     ) -> Bool {
-        bypassesStyleLearningCharacterGate || corpus.isReady
+        corpus.effectiveCharacterCount >= styleLearningMinimumCharacterCount
     }
 
     private var learnedStylePack: PolishStylePack? {
@@ -185,7 +189,7 @@ struct PolishStylesView: View {
 
     private var styleLearningCard: some View {
         let corpus = styleLearningCorpus
-        let required = PolishStyleLearningCorpusBuilder.requiredEffectiveCharacterCount
+        let required = styleLearningMinimumCharacterCount
         let reachedLimit = catalog.entries.count >= PolishStyleLimits.maximumUserPacks
         let isActionAvailable = isEligibleForStyleGeneration(corpus) && !reachedLimit
         let canGenerate = isActionAvailable && !isGeneratingLearnedStyle
@@ -240,13 +244,17 @@ struct PolishStylesView: View {
                 Spacer()
 
                 Text(
-                    bypassesStyleLearningCharacterGate && !corpus.isReady
-                        ? AppL10n.string("polishStyles.learn.testBuildReady")
-                        : corpus.isReady
+                    isEligibleForStyleGeneration(corpus)
                         ? AppL10n.string("polishStyles.learn.ready")
                         : AppL10n.format(
                             "polishStyles.learn.remaining",
-                            Int64(corpus.remainingCharacterCount)
+                            Int64(
+                                max(
+                                    0,
+                                    styleLearningMinimumCharacterCount
+                                        - corpus.effectiveCharacterCount
+                                )
+                            )
                         )
                 )
                 .font(TypeStyle.caption2)

OSGKeyboard/Views/ReleaseNotesScreenshotHarness.swift

@@ -134,7 +134,8 @@ private struct PolishStylesServiceUITestHarness: View {
                             outputLanguage: language,
                             minimumEffectiveCharacterCount:
                                 AppDistributionChannel.allowsInternalTools
-                                    ? 0
+                                    ? PolishStyleLearningCorpusBuilder
+                                        .testBuildEffectiveCharacterCount
                                     : PolishStyleLearningCorpusBuilder
                                         .requiredEffectiveCharacterCount
                         )

OSGKeyboard/en.lproj/Localizable.strings

@@ -128,6 +128,7 @@
 "common.continue" = "Continue";
 "common.reset" = "Reset";
 "common.cancel" = "Cancel";
+"common.dismiss" = "Dismiss";
 "common.save" = "Save";
 "common.clear" = "Clear";
 "common.delete" = "Delete";
@@ -294,7 +295,7 @@
 "settings.diagnostics.corpus.section" = "Personal Style Training Corpus";
 "settings.diagnostics.corpus.count" = "%d eligible samples · %d effective characters";
 "settings.diagnostics.corpus.empty" = "No eligible paired dictations are available.";
-"settings.diagnostics.corpus.ready" = "Newest complete samples through the 2,500-character target.";
+"settings.diagnostics.corpus.ready" = "Newest complete samples through the 5,000-character export cap.";
 "settings.diagnostics.corpus.export" = "Export Training Corpus";
 "settings.diagnostics.corpus.privacy" = "Contains dictated text and prior polish prompts. Nothing is uploaded automatically. Share only with trusted devices or services.";
 "settings.diagnostics.privacy.section" = "Privacy";
@@ -683,7 +684,6 @@
 "polishStyles.learn.progress" = "%lld / %lld characters";
 "polishStyles.learn.remaining" = "%lld to go";
 "polishStyles.learn.ready" = "Ready";
-"polishStyles.learn.testBuildReady" = "Test build: 2,500-character limit disabled";
 "polishStyles.learn.action" = "Generate Style";
 "polishStyles.learn.generating" = "Generating…";
 "polishStyles.learn.generated.description" = "Your personal style learned from reviewed evidence.";
@@ -959,6 +959,8 @@
 "account.referral.status.rewarded" = "Rewarded";
 "account.referral.status.ineligible" = "Ineligible";
 "account.referral.pendingAfterSignIn" = "Your invitation is saved and will be redeemed after sign-in.";
+"account.referral.rewardGranted" = "You received %@ credits from the invitation.";
+"account.referral.rewardGrantedGeneric" = "Your invitation reward has been added to your balance.";
 "account.security.section" = "Account controls";
 "account.signOut.action" = "Sign Out";
 "account.signOut.confirmTitle" = "Sign out?";

OSGKeyboard/zh-Hans.lproj/Localizable.strings

@@ -128,6 +128,7 @@
 "common.continue" = "继续";
 "common.reset" = "重置";
 "common.cancel" = "取消";
+"common.dismiss" = "关闭";
 "common.save" = "保存";
 "common.clear" = "清空";
 "common.delete" = "删除";
@@ -294,7 +295,7 @@
 "settings.diagnostics.corpus.section" = "个人风格训练语料";
 "settings.diagnostics.corpus.count" = "%d 条可用样本 · %d 个有效字符";
 "settings.diagnostics.corpus.empty" = "暂无符合条件的成对听写语料。";
-"settings.diagnostics.corpus.ready" = "选取最新完整样本，累积至至少 2,500 个有效字符。";
+"settings.diagnostics.corpus.ready" = "选取最新完整样本，导出时最多累积 5,000 个有效字符。";
 "settings.diagnostics.corpus.export" = "导出训练语料";
 "settings.diagnostics.corpus.privacy" = "文件包含口述文本和历史润色提示词，不会自动上传。请仅分享给可信设备或服务。";
 "settings.diagnostics.privacy.section" = "隐私";
@@ -682,7 +683,6 @@
 "polishStyles.learn.progress" = "%lld / %lld 字";
 "polishStyles.learn.remaining" = "还差 %lld 字";
 "polishStyles.learn.ready" = "可以生成";
-"polishStyles.learn.testBuildReady" = "测试版本：已暂时取消 2500 字限制";
 "polishStyles.learn.action" = "生成风格";
 "polishStyles.learn.generating" = "生成中…";
 "polishStyles.learn.generated.description" = "根据经过确认的证据学习得到的个人表达风格。";
@@ -958,6 +958,8 @@
 "account.referral.status.rewarded" = "已奖励";
 "account.referral.status.ineligible" = "不符合条件";
 "account.referral.pendingAfterSignIn" = "邀请已暂存，登录后会自动兑换。";
+"account.referral.rewardGranted" = "恭喜获得 %@ 积分";
+"account.referral.rewardGrantedGeneric" = "邀请奖励已发放，积分已到账。";
 "account.security.section" = "账号操作";
 "account.signOut.action" = "退出登录";
 "account.signOut.confirmTitle" = "退出登录？";