mech nitrogen filtering 2 (#19868)

* target oxygen logic

* filter out nitrogen when low on oxygen

* vvrw and datafield for everything

* :trollface:

* bruh does work

* tagless chicken

* move into atmos, make it not depend on mech

* update mech prototype

---------

Co-authored-by: deltanedas <@deltanedas:kde.org>

Content.Server/Atmos/Components/AirIntakeComponent.cs

@@ -0,0 +1,29 @@
+using Content.Server.Atmos.EntitySystems;
+using Content.Shared.Atmos;
+
+namespace Content.Server.Atmos.Components;
+
+/// <summary>
+/// This is basically a siphon vent for <see cref="GetFilterAirEvent"/>.
+/// </summary>
+[RegisterComponent, Access(typeof(AirFilterSystem))]
+public sealed partial class AirIntakeComponent : Component
+{
+    /// <summary>
+    /// Target pressure change for a single atmos tick
+    /// </summary>
+    [DataField, ViewVariables(VVAccess.ReadWrite)]
+    public float TargetPressureChange = 5f;
+
+    /// <summary>
+    /// How strong the intake pump is, it will be able to replenish air from lower pressure areas.
+    /// </summary>
+    [DataField, ViewVariables(VVAccess.ReadWrite)]
+    public float PumpPower = 2f;
+
+    /// <summary>
+    /// Pressure to intake gases up to, maintains pressure of the air volume.
+    /// </summary>
+    [DataField, ViewVariables(VVAccess.ReadWrite)]
+    public float Pressure = Atmospherics.OneAtmosphere;
+}