Halvar, God of Battle not Equiping

**Describe the bug**
The "At the beginning of combat" trigger for Halvar, God of Battle is not equiping.

**To Reproduce**
Steps to reproduce the behavior:
1. Halvar is on the field. Available Equipment is on the field. Both Halvar and the equipment are valid targets for the triggered ability.
2. I enter a combat.
3. Trigger goes on the stack.
4. I click "OK" to acknowledge the trigger.
5. I click "YES" to use the ability of Halvar.
6. Nothing Happens. The trigger is removed from the stack.

**Expected behavior**
A clear and concise description of what you expected to happen.
1. I would expect, based on similar triggers, after step 5 that I would select available equipment, then select a legal target for the equipment.
2. The trigger would resolve by attaching the equipment to the creature.

**Screenshots**
If applicable, add screenshots to help explain your problem.

**Desktop (please complete the following information):**
- OS: Windows
- Latest Version of Forger: 2.0.14-SNAPSHOT-08.08

**Smartphone (please complete the following information):**
- Device: [e.g. iPhone6]
- OS: [e.g. iOS8.1]
- Version [e.g. 22]

**Additional context**
Add any other context about the problem here.

Reproduce the issue in Forge 2.0.14-SNAPSHOT-08.08 using the listed Halvar and equipment setup, then trace Halvar, God of Battle's beginning-of-combat trigger and its resolution. Done means the trigger lets the player choose valid equipment and a legal creature, then attaches the equipment as expected.

Written by the indexing model from the issue text.