fix(localization): merge duplicate top-level "checks" block in en/de.json

en.json and de.json each defined the checks object twice; JSON silently
kept the second block's values, so the first block's friendlier titles/hints
(e.g. "Permission Mode" over the raw "--permission-mode auto support" flag)
were dead text. Merged into one block per key, keeping the friendlier title
and the more actionable hint.

Added a Utf8JsonReader-based duplicate-top-level-key test, since
JsonDocument accepts duplicates without error and the existing parity test
can't see this failure mode either.

src/ClaudeDo.Localization/locales/de.json

@@ -670,35 +670,35 @@
   "checks": {
     "git": {
       "title": "Git",
-      "hint": "Installiere Git und stelle sicher, dass es im PATH liegt."
+      "hint": "Installiere Git von https://git-scm.com/downloads und starte den Installer neu."
     },
     "gitIdentity": {
       "title": "Git-Identität",
-      "hint": "Lege deine Git-Identität fest: git config --global user.name \"...\" und user.email \"...\"."
+      "hint": "Führe aus: git config --global user.name \"Dein Name\" und git config --global user.email \"du@example.com\""
     },
     "ports": {
       "title": "Ports",
-      "hint": "Gib den Port frei oder ändere ihn nach der Installation auf der Worker-Seite."
+      "hint": "Ändere die SignalR-/MCP-Ports auf der Dienste-Seite, oder beende den blockierenden Prozess."
     },
     "writeAccess": {
       "title": "Schreibzugriff",
-      "hint": "Wähle ein anderes Installationsverzeichnis oder starte den Installer als Administrator."
+      "hint": "Wähle ein anderes Installationsverzeichnis oder starte den Installer mit ausreichenden Rechten (z. B. als Administrator)."
     },
     "claudeCli": {
       "title": "Claude CLI",
-      "hint": "Installiere die Claude CLI und stelle sicher, dass sie im PATH liegt."
+      "hint": "Installiere die Claude CLI (npm install -g @anthropic-ai/claude-code) und starte danach dein Terminal/deine Anmeldesitzung neu, damit der aktualisierte PATH greift."
     },
     "claudeVersion": {
       "title": "Claude-CLI-Version",
-      "hint": "Aktualisiere die Claude CLI auf eine neuere Version."
+      "hint": "Aktualisiere die CLI: npm update -g @anthropic-ai/claude-code"
     },
     "claudeAuth": {
-      "title": "Claude-Anmeldung",
+      "title": "Claude-CLI-Login",
-      "hint": "Führe 'claude auth login' aus, um dich anzumelden."
+      "hint": "Starte 'claude' einmal und schließe den Login-Vorgang ab."
     },
     "permissionModeAuto": {
       "title": "Berechtigungsmodus",
-      "hint": "Aktualisiere die Claude CLI auf eine Version, die --permission-mode auto unterstützt."
+      "hint": "Aktualisiere die CLI: npm update -g @anthropic-ai/claude-code. ClaudeDo funktioniert auch im Modus acceptEdits/default, dann mit mehr Rückfragen."
     }
   },
   "planning": {
@@ -875,39 +875,5 @@
       "lastError": "Letzter Fehler: {0}",
       "throttled": "Gedrosselt: {0}/{1} Slots ({2})"
     }
-  },
-  "checks": {
-    "git": {
-      "title": "Git",
-      "hint": "Installiere Git von https://git-scm.com/downloads und starte den Installer neu."
-    },
-    "gitIdentity": {
-      "title": "Git-Identität",
-      "hint": "Führe aus: git config --global user.name \"Dein Name\" und git config --global user.email \"du@example.com\""
-    },
-    "ports": {
-      "title": "Ports",
-      "hint": "Ändere die SignalR-/MCP-Ports auf der Dienste-Seite, oder beende den blockierenden Prozess."
-    },
-    "writeAccess": {
-      "title": "Schreibzugriff",
-      "hint": "Wähle ein anderes Installationsverzeichnis oder starte den Installer mit ausreichenden Rechten (z. B. als Administrator)."
-    },
-    "claudeCli": {
-      "title": "Claude CLI",
-      "hint": "Installiere die Claude CLI (npm install -g @anthropic-ai/claude-code) und starte danach dein Terminal/deine Anmeldesitzung neu, damit der aktualisierte PATH greift."
-    },
-    "claudeVersion": {
-      "title": "Claude-CLI-Version",
-      "hint": "Aktualisiere die CLI: npm update -g @anthropic-ai/claude-code"
-    },
-    "claudeAuth": {
-      "title": "Claude-CLI-Login",
-      "hint": "Starte 'claude' einmal und schließe den Login-Vorgang ab."
-    },
-    "permissionModeAuto": {
-      "title": "Unterstützung für --permission-mode auto",
-      "hint": "Aktualisiere die CLI: npm update -g @anthropic-ai/claude-code. ClaudeDo funktioniert auch im Modus acceptEdits/default, dann mit mehr Rückfragen."
-    }
   }
 }

src/ClaudeDo.Localization/locales/en.json

@@ -670,35 +670,35 @@
   "checks": {
     "git": {
       "title": "Git",
-      "hint": "Install Git and make sure it is on PATH."
+      "hint": "Install Git from https://git-scm.com/downloads, then restart the installer."
     },
     "gitIdentity": {
       "title": "Git Identity",
-      "hint": "Set your git identity: git config --global user.name \"...\" and user.email \"...\"."
+      "hint": "Run: git config --global user.name \"Your Name\" and git config --global user.email \"you@example.com\""
     },
     "ports": {
       "title": "Ports",
-      "hint": "Free the port, or change it on the Worker page after install."
+      "hint": "Change the SignalR/MCP ports on the Service page, or stop the process using them."
     },
     "writeAccess": {
       "title": "Write Access",
-      "hint": "Choose a different install directory, or run the installer as administrator."
+      "hint": "Choose a different install directory, or run the installer with sufficient permissions (e.g. as administrator)."
     },
     "claudeCli": {
       "title": "Claude CLI",
-      "hint": "Install the Claude CLI and make sure it is on PATH."
+      "hint": "Install the Claude CLI (npm install -g @anthropic-ai/claude-code), then restart your terminal/login session so the updated PATH takes effect."
     },
     "claudeVersion": {
       "title": "Claude CLI Version",
-      "hint": "Update the Claude CLI to a newer version."
+      "hint": "Update the CLI: npm update -g @anthropic-ai/claude-code"
     },
     "claudeAuth": {
-      "title": "Claude Login",
+      "title": "Claude CLI Login",
-      "hint": "Run 'claude auth login' to sign in."
+      "hint": "Run 'claude' once and complete the login flow."
     },
     "permissionModeAuto": {
       "title": "Permission Mode",
-      "hint": "Update the Claude CLI to a version that supports --permission-mode auto."
+      "hint": "Update the CLI: npm update -g @anthropic-ai/claude-code. ClaudeDo still works in acceptEdits/default mode, with more prompts."
     }
   },
   "planning": {
@@ -875,39 +875,5 @@
       "lastError": "Last error: {0}",
       "throttled": "Throttled: {0}/{1} slots ({2})"
     }
-  },
-  "checks": {
-    "git": {
-      "title": "Git",
-      "hint": "Install Git from https://git-scm.com/downloads, then restart the installer."
-    },
-    "gitIdentity": {
-      "title": "Git identity",
-      "hint": "Run: git config --global user.name \"Your Name\" and git config --global user.email \"you@example.com\""
-    },
-    "ports": {
-      "title": "Ports",
-      "hint": "Change the SignalR/MCP ports on the Service page, or stop the process using them."
-    },
-    "writeAccess": {
-      "title": "Write access",
-      "hint": "Choose a different install directory, or run the installer with sufficient permissions (e.g. as administrator)."
-    },
-    "claudeCli": {
-      "title": "Claude CLI",
-      "hint": "Install the Claude CLI (npm install -g @anthropic-ai/claude-code), then restart your terminal/login session so the updated PATH takes effect."
-    },
-    "claudeVersion": {
-      "title": "Claude CLI version",
-      "hint": "Update the CLI: npm update -g @anthropic-ai/claude-code"
-    },
-    "claudeAuth": {
-      "title": "Claude CLI login",
-      "hint": "Run 'claude' once and complete the login flow."
-    },
-    "permissionModeAuto": {
-      "title": "--permission-mode auto support",
-      "hint": "Update the CLI: npm update -g @anthropic-ai/claude-code. ClaudeDo still works in acceptEdits/default mode, with more prompts."
-    }
   }
 }

tests/ClaudeDo.Localization.Tests/DuplicateLocaleKeysTests.cs

@@ -0,0 +1,84 @@
+using System.Text;
+using System.Text.Json;
+
+namespace ClaudeDo.Localization.Tests;
+
+/// <summary>
+/// JsonDocument/JsonElement silently keep the last value on a duplicate key instead of throwing,
+/// so a repeated top-level block (e.g. two "checks" objects) is invisible to JSON-validity and
+/// parity tests alike. This walks the raw token stream instead.
+/// </summary>
+public class DuplicateLocaleKeysTests
+{
+    private static string LocalesDir()
+    {
+        var dir = AppContext.BaseDirectory;
+        while (dir is not null)
+        {
+            var candidate = Path.Combine(dir, "src", "ClaudeDo.Localization", "locales");
+            if (Directory.Exists(candidate)) return candidate;
+            dir = Path.GetDirectoryName(dir);
+        }
+        throw new DirectoryNotFoundException("Could not locate src/ClaudeDo.Localization/locales");
+    }
+
+    private static List<string> FindDuplicateTopLevelKeys(string json)
+    {
+        var reader = new Utf8JsonReader(Encoding.UTF8.GetBytes(json));
+        var seen = new HashSet<string>(StringComparer.Ordinal);
+        var duplicates = new List<string>();
+        var depth = 0;
+
+        while (reader.Read())
+        {
+            switch (reader.TokenType)
+            {
+                case JsonTokenType.StartObject:
+                case JsonTokenType.StartArray:
+                    depth++;
+                    break;
+                case JsonTokenType.EndObject:
+                case JsonTokenType.EndArray:
+                    depth--;
+                    break;
+                case JsonTokenType.PropertyName:
+                    if (depth == 1)
+                    {
+                        var name = reader.GetString()!;
+                        if (!seen.Add(name)) duplicates.Add(name);
+                    }
+                    break;
+            }
+        }
+
+        return duplicates;
+    }
+
+    [Fact]
+    public void Detects_duplicate_top_level_key_in_fixture()
+    {
+        const string json = """
+        {
+          "checks": { "a": "1" },
+          "other": { "b": "2" },
+          "checks": { "c": "3" }
+        }
+        """;
+
+        var duplicates = FindDuplicateTopLevelKeys(json);
+
+        Assert.Contains("checks", duplicates);
+    }
+
+    [Fact]
+    public void Locale_files_have_no_duplicate_top_level_keys()
+    {
+        var localesDir = LocalesDir();
+        foreach (var path in Directory.EnumerateFiles(localesDir, "*.json"))
+        {
+            var duplicates = FindDuplicateTopLevelKeys(File.ReadAllText(path));
+            Assert.True(duplicates.Count == 0,
+                $"{Path.GetFileName(path)} has duplicate top-level keys: {string.Join(", ", duplicates)}");
+        }
+    }
+}