feat(types): add llms-txt type definitions

Add AgentFile and LlmsTxtResult interfaces for llms.txt generation
and export from the shared types barrel.

Author: lukeocodes

shared/types/index.ts

@@ -11,3 +11,4 @@ export * from './skills'
 export * from './compare'
 export * from './version-downloads'
 export * from './install-size'
+export * from './llms-txt'

shared/types/llms-txt.ts

@@ -0,0 +1,31 @@
+/**
+ * Agent instruction file discovered in a package
+ */
+export interface AgentFile {
+  /** Relative path within the package (e.g., "CLAUDE.md", ".github/copilot-instructions.md") */
+  path: string
+  /** File content */
+  content: string
+  /** Human-readable display name (e.g., "Claude Code", "GitHub Copilot") */
+  displayName: string
+}
+
+/**
+ * Result of gathering all data needed to generate llms.txt
+ */
+export interface LlmsTxtResult {
+  /** Package name (e.g., "nuxt" or "@nuxt/kit") */
+  packageName: string
+  /** Resolved version (e.g., "3.12.0") */
+  version: string
+  /** Package description from packument */
+  description?: string
+  /** Homepage URL */
+  homepage?: string
+  /** Repository URL */
+  repositoryUrl?: string
+  /** README content (raw markdown) */
+  readme?: string
+  /** Discovered agent instruction files */
+  agentFiles: AgentFile[]
+}