[TF2] Fix Half-Zatoichi honor kill being survivable with damage reduction runes

[PhiTiet]

Fixes ValveSoftware/Source-1-Games#6974

The honor-bound one-shot uses GetHealth() * 3. The Resist rune's 0.5x multiplier applied downstream can reduce this below lethal, especially when stacked with other reductions. Increased to * 10.

[JoriKos]

It's what I initially did on #1691 except with * 5. Currently working on a solution to properly add a new damage type for it and check for that instead, as simply bypassing the resistance is much cleaner than just upping the damage by a ton.

[PhiTiet]

@JoriKos Your exact suggestion is implemented correctly now: the Half-Zatoichi honor-bound duel kill uses a dedicated custom damage type and cleanly bypasses resist-rune reduction instead of inflating the damage value.

[JoriKos]

Now it's pretty much the same as my PR, but it doesn't bypass regular damage resistance. Issue is that basically copying #1691 isn't very productive unless it superceeds it.