docs: hold the documentation against the code

Every claim in the user-facing docs, checked against what the plugin
actually does after A2 to A5.

The two GDPR sections in PRIVACY.md describe features that only exist
again as of this cycle, so they now name the screens they live on and
say what the cleanup does with a channel this build does not recognise.
The export sentence promised a date range; the form offers an age in
days.

PRIVACY.md also named "Show emotes" in Settings as the way to stop the
one outbound call the plugin makes. That switch has had no control since
May, and a documented opt-out that only exists in the JSON is not an
opt-out, so the toggle is back in the chat tab. Both its strings were
already translated.

Dead paths: the README source tree still listed a file deleted in May,
docs/IPC.md cited a window that no longer exists, the first-run wizard
pointed at the same removed file, and the theme authoring guide sent
readers to a Themes tab that is called Appearance.

The changelog lost two double blank lines that were failing markdownlint
and holding preflight red. Preflight is green again.

Historical documents keep their old paths on purpose: the changelog and
the AI disclosure describe what was true when they were written.

HellionChat/Ui/Components/Settings/Tabs/ChatTab.cs

@@ -34,6 +34,17 @@ internal sealed class ChatTab
                 v => Plugin.Config.Use24HourClock = v
             );
 
+            // PRIVACY.md names this switch as the way to stop the one outbound
+            // call the plugin makes, and it has had no control since May. A
+            // documented opt-out that only exists in the JSON is not an opt-out.
+            _w.ToggleRow(
+                ImGui.GetID("chat.display.emotes"u8),
+                Language.Options_ShowEmotes_Name,
+                Language.Options_ShowEmotes_Desc,
+                () => Plugin.Config.ShowEmotes,
+                v => Plugin.Config.ShowEmotes = v
+            );
+
             // Descriptions move out of the help markers and onto the row. They
             // were written to be read; a (?) the user has to hover is where an
             // explanation goes to be ignored.

HellionChat/Ui/FirstRunWizard.cs

@@ -368,7 +368,9 @@ public sealed class FirstRunWizard : Window
             // Mirror the DataAndPrivacy coupling: turning load-previous on
             // also turns filter-include on (otherwise old messages bypass
             // the filter chain), and turning filter-include off forces
-            // load-previous off. Same idiom as Ui/SettingsTabs/DataAndPrivacy.cs.
+            // load-previous off. The settings tab that used to hold the same
+            // pairing was removed in May; the coupling lives here alone until
+            // the two checkboxes are reachable again.
             if (loadPrev)
                 _state.PendingFilterIncludePreviousSessions = true;
         }