fix: enhance node type format normalization for better AI agent compatibility (Issue #74)

- Added support for n8n-nodes-langchain.* → nodes-langchain.* normalization
- Implemented case-insensitive node name matching (e.g., chattrigger → chatTrigger)
- Added smart camelCase detection for common patterns (trigger, request, sheets, etc.)
- Fixed get_node_documentation tool to use same normalization logic as other tools
- Updated all 7 node lookup locations to use normalized types for alternatives
- Enhanced getNodeTypeAlternatives() to normalize all generated alternatives

All MCP tools now consistently handle various format variations:
- nodes-langchain.chatTrigger (correct format)
- n8n-nodes-langchain.chatTrigger (package format)
- n8n-nodes-langchain.chattrigger (package + wrong case)
- nodes-langchain.chattrigger (wrong case only)
- @n8n/n8n-nodes-langchain.chatTrigger (full npm format)

Bump version to 2.7.19

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/utils/node-utils.ts

@@ -4,6 +4,7 @@
  * Examples:
  * - 'n8n-nodes-base.httpRequest' → 'nodes-base.httpRequest'
  * - '@n8n/n8n-nodes-langchain.agent' → 'nodes-langchain.agent'
+ * - 'n8n-nodes-langchain.chatTrigger' → 'nodes-langchain.chatTrigger'
  * - 'nodes-base.slack' → 'nodes-base.slack' (unchanged)
  * 
  * @param nodeType The node type to normalize
@@ -20,6 +21,11 @@ export function normalizeNodeType(nodeType: string): string {
     return nodeType.replace('@n8n/n8n-nodes-langchain.', 'nodes-langchain.');
   }
   
+  // Handle n8n-nodes-langchain -> nodes-langchain (without @n8n/ prefix)
+  if (nodeType.startsWith('n8n-nodes-langchain.')) {
+    return nodeType.replace('n8n-nodes-langchain.', 'nodes-langchain.');
+  }
+  
   // Return unchanged if already normalized or unknown format
   return nodeType;
 }
@@ -36,13 +42,86 @@ export function getNodeTypeAlternatives(nodeType: string): string[] {
   // Add lowercase version
   alternatives.push(nodeType.toLowerCase());
   
+  // If it has a prefix, try case variations on the node name part
+  if (nodeType.includes('.')) {
+    const [prefix, nodeName] = nodeType.split('.');
+    
+    // Try different case variations for the node name
+    if (nodeName && nodeName.toLowerCase() !== nodeName) {
+      alternatives.push(`${prefix}.${nodeName.toLowerCase()}`);
+    }
+    
+    // For camelCase names like "chatTrigger", also try with capital first letter variations
+    // e.g., "chattrigger" -> "chatTrigger"
+    if (nodeName && nodeName.toLowerCase() === nodeName && nodeName.length > 1) {
+      // Try to detect common patterns and create camelCase version
+      const camelCaseVariants = generateCamelCaseVariants(nodeName);
+      camelCaseVariants.forEach(variant => {
+        alternatives.push(`${prefix}.${variant}`);
+      });
+    }
+  }
+  
   // If it's just a bare node name, try with common prefixes
   if (!nodeType.includes('.')) {
     alternatives.push(`nodes-base.${nodeType}`);
     alternatives.push(`nodes-langchain.${nodeType}`);
+    
+    // Also try camelCase variants for bare names
+    const camelCaseVariants = generateCamelCaseVariants(nodeType);
+    camelCaseVariants.forEach(variant => {
+      alternatives.push(`nodes-base.${variant}`);
+      alternatives.push(`nodes-langchain.${variant}`);
+    });
   }
   
-  return alternatives;
+  // Normalize all alternatives and combine with originals
+  const normalizedAlternatives = alternatives.map(alt => normalizeNodeType(alt));
+  
+  // Combine original alternatives with normalized ones and remove duplicates
+  return [...new Set([...alternatives, ...normalizedAlternatives])];
+}
+
+/**
+ * Generate camelCase variants for a lowercase string
+ * @param str The lowercase string
+ * @returns Array of possible camelCase variants
+ */
+function generateCamelCaseVariants(str: string): string[] {
+  const variants: string[] = [];
+  
+  // Common patterns for n8n nodes
+  const patterns = [
+    // Pattern: wordTrigger (e.g., chatTrigger, webhookTrigger)
+    /^(.+)(trigger|node|request|response)$/i,
+    // Pattern: httpRequest, mysqlDatabase
+    /^(http|mysql|postgres|mongo|redis|mqtt|smtp|imap|ftp|ssh|api)(.+)$/i,
+    // Pattern: googleSheets, microsoftTeams
+    /^(google|microsoft|amazon|slack|discord|telegram)(.+)$/i,
+  ];
+  
+  for (const pattern of patterns) {
+    const match = str.toLowerCase().match(pattern);
+    if (match) {
+      const [, first, second] = match;
+      // Capitalize the second part
+      variants.push(first.toLowerCase() + second.charAt(0).toUpperCase() + second.slice(1).toLowerCase());
+    }
+  }
+  
+  // Generic camelCase: capitalize after common word boundaries
+  if (variants.length === 0) {
+    // Try splitting on common boundaries and capitalizing
+    const words = str.split(/[-_\s]+/);
+    if (words.length > 1) {
+      const camelCase = words[0].toLowerCase() + words.slice(1).map(w => 
+        w.charAt(0).toUpperCase() + w.slice(1).toLowerCase()
+      ).join('');
+      variants.push(camelCase);
+    }
+  }
+  
+  return variants;
 }
 
 /**