Display phase emblems in the middle panel

This patch introduces phase emblems on both sides of the player's name
band in the middle panel. The emblems represent the current phase of
the selected player's civilization: I (Village), II (Town), III (City).
This information is also added to the associated tooltip and is
displayed only to mutual allies and observers.

Fixes #6849
See also: https://wildfiregames.com/forum/topic/107851-introduce-badge-to-indicate-the-phase-6849/

binaries/data/mods/public/gui/session/selection_details.js

@@ -317,9 +317,31 @@ function displaySingle(entState)
 		});
 	secondaryObject.hidden = hideSecondary;
 
-	let isGaia = playerState.civ == "gaia";
+	const isGaia = playerState.civ == "gaia";
 	Engine.GetGUIObjectByName("playerCivIcon").sprite = isGaia ? "" : "cropped:1.0, 0.15625 center:grayscale:" + civEmblem;
-	Engine.GetGUIObjectByName("civilizationTooltip").tooltip = isGaia ? "" : civName;
+
+	if (isGaia)
+	{
+		Engine.GetGUIObjectByName("phaseEmblems").sprite = "";
+		Engine.GetGUIObjectByName("civilizationTooltip").tooltip = "";
+	}
+	else
+	{
+		let civilizationTooltip = civName;
+		let civPhaseEmblems = "session/panel_phase_emblems_hidden.png";
+
+		// Reveal phases to mutual allies and observers
+		if (g_ViewedPlayer == -1 || playerState.isMutualAlly[g_ViewedPlayer])
+		{
+			const civPhase = g_SimState.players[entState.player].phase
+			civPhaseEmblems = "session/panel_phase_emblems_" + civPhase + ".png";
+			const civPhaseData = GetTechnologyData("phase_" + civPhase + "_" + playerState.civ, playerState.civ) ||
+				GetTechnologyData("phase_" + civPhase, playerState.civ);
+			civilizationTooltip += " — " + getEntityNames(civPhaseData);
+		}
+		Engine.GetGUIObjectByName("phaseEmblems").sprite = "cropped:1.0, 1.0 center:" + civPhaseEmblems;
+		Engine.GetGUIObjectByName("civilizationTooltip").tooltip = civilizationTooltip;
+	}
 
 	// TODO: we should require all entities to have icons
 	Engine.GetGUIObjectByName("icon").sprite = template.icon ? ("stretched:session/portraits/" + template.icon) : "BackgroundBlack";

binaries/data/mods/public/gui/session/selection_panels_middle/single_details_area.xml

@@ -12,6 +12,8 @@
 			<object size="50%-64 50%-10 50%+64 50%+10" name="playerCivIcon" type="image" ghost="true"/>
 			<!-- Player color band. -->
 			<object name="playerColorBackground" type="image" sprite="playerColorBackground" ghost="true"/>
+			<!-- Phase emblems. -->
+			<object size="0 0 100% 100%" name="phaseEmblems" type="image" ghost="true"/>
 			<object type="image" sprite="bottomEdgedPanelShader" ghost="true"/>
 			<!-- Player name. -->
 			<object size="0 50%-10 100% 50%+10" name="player" type="text" style="largeCenteredOutlinedText"/>