refactor: modularize claude-executor and extract shared utilities

- Extract message handling into src/ai/message-handlers.ts with pure functions
- Extract output formatting into src/ai/output-formatters.ts
- Extract progress management into src/ai/progress-manager.ts
- Add audit-logger.ts with Null Object pattern for optional logging
- Add shared utilities: formatting.ts, file-io.ts, functional.ts
- Consolidate getPromptNameForAgent into src/types/agents.ts

src/types/agents.ts

@@ -47,10 +47,6 @@ export type PlaywrightAgent =
 
 export type AgentValidator = (sourceDir: string) => Promise<boolean>;
 
-export type AgentValidatorMap = Record<AgentName, AgentValidator>;
-
-export type McpAgentMapping = Record<PromptName, PlaywrightAgent>;
-
 export type AgentStatus =
   | 'pending'
   | 'in_progress'
@@ -63,3 +59,26 @@ export interface AgentDefinition {
   displayName: string;
   prerequisites: AgentName[];
 }
+
+/**
+ * Maps an agent name to its corresponding prompt file name.
+ */
+export function getPromptNameForAgent(agentName: AgentName): PromptName {
+  const mappings: Record<AgentName, PromptName> = {
+    'pre-recon': 'pre-recon-code',
+    'recon': 'recon',
+    'injection-vuln': 'vuln-injection',
+    'xss-vuln': 'vuln-xss',
+    'auth-vuln': 'vuln-auth',
+    'ssrf-vuln': 'vuln-ssrf',
+    'authz-vuln': 'vuln-authz',
+    'injection-exploit': 'exploit-injection',
+    'xss-exploit': 'exploit-xss',
+    'auth-exploit': 'exploit-auth',
+    'ssrf-exploit': 'exploit-ssrf',
+    'authz-exploit': 'exploit-authz',
+    'report': 'report-executive',
+  };
+
+  return mappings[agentName];
+}