feat: add Discuss and Explore subagents for dynamic critique and code exploration

- Implement Discuss Subagent for multi-perspective critique with dynamic perspectives.
- Create Explore Subagent for shared codebase exploration with centralized caching.
- Add tests for CcwToolsMcpCard component to ensure enabled tools are preserved on config save.
- Introduce SessionPreviewPanel component for previewing and selecting sessions for Memory V2 extraction.
- Develop CommandCreateDialog component for creating/importing commands with import and CLI generate modes.

ccw/frontend/src/locales/en/commands.json

@@ -10,7 +10,8 @@
     "collapseAll": "Collapse All",
     "copy": "Copy",
     "showDisabled": "Show Disabled",
-    "hideDisabled": "Hide Disabled"
+    "hideDisabled": "Hide Disabled",
+    "cancel": "Cancel"
   },
   "source": {
     "builtin": "Built-in",
@@ -57,5 +58,45 @@
     "clickToDisableAll": "Click to disable all",
     "noCommands": "No commands in this group",
     "noEnabledCommands": "No enabled commands in this group"
+  },
+  "create": {
+    "title": "Create Command",
+    "location": "Location",
+    "locationProject": "Project Commands",
+    "locationProjectHint": ".claude/commands/",
+    "locationUser": "Global Commands",
+    "locationUserHint": "~/.claude/commands/",
+    "mode": "Creation Mode",
+    "modeImport": "Import File",
+    "modeImportHint": "Import command from existing file",
+    "modeGenerate": "AI Generate",
+    "modeGenerateHint": "Generate command using AI",
+    "sourcePath": "Source File Path",
+    "sourcePathPlaceholder": "Enter absolute path to command file",
+    "sourcePathHint": "File must be a valid command markdown file",
+    "customName": "Custom Name",
+    "customNamePlaceholder": "Leave empty to use original name",
+    "customNameHint": "Optional, overrides default command name",
+    "commandName": "Command Name",
+    "commandNamePlaceholder": "Enter command name",
+    "commandNameHint": "Used as the command file name",
+    "descriptionLabel": "Command Description",
+    "descriptionPlaceholder": "Describe what this command should do...",
+    "descriptionHint": "AI will generate command content based on this description",
+    "generateInfo": "AI will use CLI tools to generate the command",
+    "generateTimeHint": "Generation may take some time",
+    "validate": "Validate",
+    "import": "Import",
+    "generate": "Generate",
+    "validating": "Validating...",
+    "validCommand": "Validation passed",
+    "invalidCommand": "Validation failed",
+    "creating": "Creating...",
+    "created": "Command \"{name}\" created successfully",
+    "createError": "Failed to create command",
+    "sourcePathRequired": "Please enter source file path",
+    "commandNameRequired": "Please enter command name",
+    "descriptionRequired": "Please enter command description",
+    "validateFirst": "Please validate the command file first"
   }
 }