fix: webhook and 4 other nodes incorrectly marked as non-triggers

Fixed issue where Docker images using sql.js adapter returned boolean fields
as strings, causing is_trigger=0 to evaluate as true instead of false.

Changes:
- Added convertIntegerColumns() to sql.js adapter to convert SQLite integers
- Updated server.ts and node-repository.ts to use Number() conversion as backup
- Added test script to verify fix works with sql.js adapter

This fixes webhook, cron, interval, and emailReadImap nodes showing
isTrigger: false in Docker deployments.

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

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

src/database/node-repository.ts

@@ -53,10 +53,10 @@ export class NodeRepository {
       category: row.category,
       developmentStyle: row.development_style,
       package: row.package_name,
-      isAITool: !!row.is_ai_tool,
-      isTrigger: !!row.is_trigger,
-      isWebhook: !!row.is_webhook,
-      isVersioned: !!row.is_versioned,
+      isAITool: Number(row.is_ai_tool) === 1,
+      isTrigger: Number(row.is_trigger) === 1,
+      isWebhook: Number(row.is_webhook) === 1,
+      isVersioned: Number(row.is_versioned) === 1,
       version: row.version,
       properties: this.safeJsonParse(row.properties_schema, []),
       operations: this.safeJsonParse(row.operations, []),