[HL2MP] Improve PointAngleSensor accuracy for player entities

[speedvoltage]

Issue:
The CPointAngleSensor used to depend on the target entity's general forward vector, which doesn't always match up with a player's true view direction. This could lead to misalignment in systems that require precise player viewing angles, like sensors, tracking systems, or targeting mechanisms, especially when the target is a player.

Fix:
To better manage player entities, we add a check for CBasePlayer. Now, if the target is a player, it fetches the player's EyeVectors() instead of the usual GetVectors(). This ensures that the angle sensor aligns accurately with the player's actual line of sight. If the target isn't a player, it reverts to the original GetVectors() method.