RTBHouse: Extract tagid from Imp fields

[piotrj-rtbh]

🔧 Type of changes

• bid adapter update
• enhancement

✨ What's the context?

Related PR (Golang): prebid/prebid-server#4624
RTBHouse bidder was not setting imp.tagid in outgoing requests, which could impact ad targeting effectiveness. This change adds support for populating tagid from various incoming request fields with a defined priority order.

📋 Description

Adds logic to set imp.tagid in RTBHouse bid requests using fallback priority: imp.ext.gpid → imp.ext.data.adserver.adslot → imp.ext.data.pbadslot → imp.id → null. This ensures better ad targeting by providing RTBHouse with appropriate tagid values.

🧪 Testing results

Tests run: 26, Failures: 0, Errors: 0, Skipped: 0
All RTBHouse bidder tests pass successfully, including:

• Unit tests for new functionality (6 tests)
• Integration test with updated mock expectations (1 test)
• Backward compatibility verification (19 existing tests)

Other information

Please reach us at inventory_support@rtbhouse.com with piotr.jaworski@rtbhouse.com and cc leandro.otani@rtbhouse.com.