Format names of players who never joined the instance

Reports carry names from the controller, so the reported player, the
reporter or the caller may never have joined this server. The exp_util
formatter asserts the player exists, so those names now fall back to
plain white text. The test stub of the formatter now requires a LuaPlayer
like the real one, which made the existing receiver tests fail before the
fix.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

exp_reports/module/control.lua

@@ -9,7 +9,8 @@ player who asked once it arrives, if they are still online.
 local clusterio_api = require("modules/clusterio/api")
 local ExpUtil = require("modules/exp_util")
 
-local format_player_name = ExpUtil.format_player_name_locale
+local format_player_name_locale = ExpUtil.format_player_name_locale
+local format_rich_text_color_locale = ExpUtil.format_rich_text_color_locale
 
 --- @class ExpReports
 local ExpReports = {
@@ -88,6 +89,17 @@ local function get_online_player(name)
     return nil
 end
 
+--- Names come from the controller, so the player may never have joined this server
+--- @param name string
+--- @return LocalisedString
+local function format_player_name(name)
+    local player = game.get_player(name)
+    if player then
+        return format_player_name_locale(player)
+    end
+    return format_rich_text_color_locale(name, ExpUtil.color.white)
+end
+
 --- The controller accepted a report
 --- @param payload { report: ExpReports.Report, reports: ExpReports.Report[] }
 function ExpReports.receive_created(payload)

exp_reports/test/module/env.lua

@@ -23,8 +23,12 @@ return Framework.suite(function(env)
     --- @cast env ExpReports.TestEnv
     env.extend_requires{
         ["modules/exp_util"] = {
-            format_player_name_locale = function(name) return name end,
-            color = { orange_red = "orange_red" },
+            format_player_name_locale = function(player)
+                assert(type(player) == "table", "format_player_name_locale takes a LuaPlayer")
+                return player.name
+            end,
+            format_rich_text_color_locale = function(message) return message end,
+            color = { orange_red = "orange_red", white = "white" },
         },
     }
     env.Reports = assert(loadfile(plugin_root .. "/module/control.lua"))() --- @type ExpReports