Sprinting spear attack lacks extra knockback parity

In Minecraft Bedrock Edition, performing a spear attack while sprinting causes the target to be knocked back further than a normal attack. This gives the weapon additional tactical depth and reward for momentum. However, in Minecraft Java Edition 26.3-snapshot-7, the spear does not receive any knockback distance bonus when sprinting. This is a parity gap between the two editions, and it significantly reduces the spear's combat utility on Java compared to Bedrock. This report requests adding the sprint-based knockback increase to the Java Edition spear, aligning it with Bedrock behavior.

Steps to Reproduce (Java current state):

1. Launch Minecraft Java Edition 26.3-snapshot-7.

2. Obtain a spear

3. Have a target (player or mob) stand nearby.

4. Attack the target with a spear thrust (left-click) while standing still and note the knockback distance.

5. Attack the target again while sprinting. Observe that the knockback distance is identical to the standing attack — no extra knockback is applied.

Expected Behavior (based on Bedrock Edition):
When sprinting, the spear attack should knock the target back noticeably further than a normal standing attack, rewarding the player's momentum.

Observed Behavior:
Sprinting does not affect spear knockback distance at all on Java Edition.

Impact:
Medium-High — This inconsistency gives Java players an inferior spear experience compared to Bedrock, and removes a skill-based mechanic that makes sprinting more meaningful in combat. Adding this feature would improve combat fluidity and parity.