Introduce thread-based help system

application/config.json.template

@@ -8,16 +8,6 @@
     "heavyModerationRolePattern": "Moderator",
     "softModerationRolePattern": "Moderator|Staff Assistant",
     "tagManageRolePattern": "Moderator|Staff Assistant|Top Helpers .+",
-    "freeCommand": [
-        {
-            "inactiveChannelDuration": "PT2H",
-            "messageRetrieveLimit": 10,
-            "statusChannel": <put_a_channel_id_here>,
-            "monitoredChannels": [
-                    <put_a_channel_id_here>
-                  ]
-        }
-   ],
    "helpChannelPattern": "([a-zA-Z_]+_)?help(_\\d+)?",
    "suggestions": {
        "channelPattern": "tj_suggestions",
@@ -33,5 +23,26 @@
        "suspiciousHostKeywords": ["discord", "nitro", "premium"],
        "isHostSimilarToKeywordDistanceThreshold": 2
    },
-   "wolframAlphaAppId": "79J52T-6239TVXHR7"
+   "wolframAlphaAppId": "79J52T-6239TVXHR7",
+   "helpSystem": {
+       "stagingChannelPattern": "ask_here",
+       "overviewChannelPattern": "active_questions",
+       "categories": [
+           "Java",
+           "Frameworks",
+           "JavaFX|Swing",
+           "IDE",
+           "Build Tools",
+           "Database",
+           "Android",
+           "C|C++",
+           "Algorithms",
+           "Math",
+           "Architecture",
+           "Code Review",
+           "Together Java Bot",
+           "Other"
+       ],
+       "categoryRoleSuffix": " - Helper"
+   }
 }

application/src/main/java/org/togetherjava/tjbot/commands/Features.java

@@ -6,9 +6,7 @@
 import org.togetherjava.tjbot.commands.basic.RoleSelectCommand;
 import org.togetherjava.tjbot.commands.basic.SuggestionsUpDownVoter;
 import org.togetherjava.tjbot.commands.basic.VcActivityCommand;
-import org.togetherjava.tjbot.commands.free.AutoFreeRoutine;
-import org.togetherjava.tjbot.commands.free.FreeChannelMonitor;
-import org.togetherjava.tjbot.commands.free.FreeCommand;
+import org.togetherjava.tjbot.commands.help.*;
 import org.togetherjava.tjbot.commands.mathcommands.TeXCommand;
 import org.togetherjava.tjbot.commands.mathcommands.wolframalpha.WolframAlphaCommand;
 import org.togetherjava.tjbot.commands.moderation.*;
@@ -62,7 +60,7 @@ public enum Features {
         ModerationActionsStore actionsStore = new ModerationActionsStore(database);
         ModAuditLogWriter modAuditLogWriter = new ModAuditLogWriter(config);
         ScamHistoryStore scamHistoryStore = new ScamHistoryStore(database);
-        FreeChannelMonitor freeChannelMonitor = new FreeChannelMonitor(config);
+        HelpSystemHelper helpSystemHelper = new HelpSystemHelper(config);
 
         // NOTE The system can add special system relevant commands also by itself,
         // hence this list may not necessarily represent the full list of all commands actually
@@ -75,12 +73,13 @@ public enum Features {
         features.add(new TopHelpersPurgeMessagesRoutine(database));
         features.add(new RemindRoutine(database));
         features.add(new ScamHistoryPurgeRoutine(scamHistoryStore));
-        features.add(new AutoFreeRoutine(freeChannelMonitor));
+        features.add(new BotMessageCleanup(config));
 
         // Message receivers
         features.add(new TopHelpersMessageListener(database, config));
         features.add(new SuggestionsUpDownVoter(config));
         features.add(new ScamBlocker(actionsStore, scamHistoryStore, config));
+        features.add(new ImplicitAskListener(config, helpSystemHelper));
 
         // Event receivers
         features.add(new RejoinModerationRoleListener(actionsStore, config));
@@ -107,9 +106,12 @@ public enum Features {
         features.add(new UnquarantineCommand(actionsStore, config));
         features.add(new WhoIsCommand());
         features.add(new WolframAlphaCommand(config));
+        features.add(new AskCommand(config, helpSystemHelper));
+        features.add(new CloseCommand(helpSystemHelper));
+        features.add(new ChangeHelpCategoryCommand(config, helpSystemHelper));
 
         // Mixtures
-        features.add(new FreeCommand(config, freeChannelMonitor));
+        features.add(new HelpThreadOverviewUpdater(config, helpSystemHelper));
 
         return features;
     }

application/src/main/java/org/togetherjava/tjbot/commands/Routine.java

@@ -16,13 +16,6 @@
  * the schedule defined by {@link #createSchedule()}.
  */
 public interface Routine extends Feature {
-    /**
-     * Triggered by the core system on the schedule defined by {@link #createSchedule()}.
-     *
-     * @param jda the JDA instance the bot is operating with
-     */
-    void runRoutine(@NotNull JDA jda);
-
     /**
      * Retrieves the schedule of this routine. Called by the core system once during the startup in
      * order to execute the routine accordingly.
@@ -34,6 +27,13 @@ public interface Routine extends Feature {
     @NotNull
     Schedule createSchedule();
 
+    /**
+     * Triggered by the core system on the schedule defined by {@link #createSchedule()}.
+     *
+     * @param jda the JDA instance the bot is operating with
+     */
+    void runRoutine(@NotNull JDA jda);
+
     /**
      * The schedule of routines.
      *