Add createTaskFlow/editTaskFlow actions

[hillary-mutisya]

TaskFlow:

• Add createTaskFlow action for direct flow registration from reasoning (name, description, parameters, script, grammarPatterns)
• Add editTaskFlow action for modifying existing flows
• Add deleteTaskFlow action for removing flows
• Extract ParameterDefinition interface from inline type in TaskFlowStore
• Expand TaskFlowStore with hasFlow(), saveFlowFromAction(), and deleteFlow() methods for CRUD operations
• Fix taskFlowScriptApi to handle both array and record parameter formats and support optional testValue fields

ScriptFlow:

• Add testScriptFlow action for test-then-register pattern — executes a script in sandbox without saving, allowing validation before registration
• Add hasFlow() to ScriptFlowStore for duplicate checking

Dispatcher:

• Expose CommandHandlerContext via _systemContext on sessionContext so agents executing nested actions (e.g., TaskFlow calling player actions) resolve the correct system context
• Fix actionHandlers to use _systemContext fallback for nested execution
• Reload dynamic schemas and grammars after schema reload in appAgentManager to pick up newly registered flows immediately