fix: backward-compat + bug fixes and man-page build fix for 0.16.0

Post-0.15.0 review of the 0.15.0..HEAD range surfaced regressions and
bugs. This restores backward compatibility for existing configs/CSS,
fixes confirmed defects, and repairs the scdoc man-page build break on
master. Pango-markup tooltips are intentional and were kept.

Backward-compat restorations:
- AModule: honor legacy numeric Gdk::CursorType cursor values (int overload)
- memory: correct GiB divisor (was ~2.3% low); round bare {} placeholders
- wireplumber: scale max-volume into the linear domain so the cap works again
- idle_inhibitor: gate right/middle-click deactivate & scroll on dynamic-timeouts;
  accept both dynamic-timeout(s); widen timeout to double (no fractional truncation)
- custom: keep #custom-<name>.<class> CSS selectors working (classes on box_)
- image: don't wordexp-split a single path; fall back to the literal path
- niri/window: restore hide-when-empty (new show-empty opt-in); escape tooltip
- wlr/taskbar: plain-text tooltip when markup is disabled

Bug fixes:
- tray: fix use-after-free in onAdd; guard the watcher retry timeout
- hyprland: clamp max-windows iterator (OOB); drop duplicate language tooltip block
- niri/window: supply {col}/{max_col} args in the empty branch (fmt::format_error)
- mpris: escape {dynamic}/{player} tooltip; fix dangling player; albumArtist source
- mango: fix use-after-free race (dispatch under callback_mutex_)
- mpd: contain throwing checkErrors in noexcept idle paths (no std::terminate/UAF)
- keyboard_state: always render every lock label, with guarded defaults
- bluetooth: bound GATT ReadValue timeout, opt-in + services-resolved gating,
  preserve authoritative Battery1 percentage
- wireplumber: fix WpDevice reference leak / NULL handling
- battery, clock, dwl, wayfire, graph, custom_graph, transform, river: assorted
  crash/logic fixes

Man page / build:
- niri-workspaces: fix scdoc "indented by an amount greater than 1"
  (workspace-taskbar sub-options were mis-indented; breaks man-page build)
- document new show-empty (niri/window); correct network {txBitrate}/{rxBitrate}

Not compiled locally (no gtkmm on this host); C++ build relies on CI.
Man pages validated with scdoc 1.11.4.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/modules/keyboard_state.cpp

@@ -86,7 +86,6 @@ auto isCommonFormatIcons(const Json::Value& config) -> bool {
 auto keyStateToIcons(const Json::Value& config)
     -> std::unordered_map<std::string, std::vector<std::string>> {
   std::unordered_map<std::string, std::vector<std::string>> key_icon_states;
-  std::vector<std::string> default_icons = {"unlocked", "locked"};
 
   if (isCommonFormatIcons(config)) {
     std::vector<std::string> icons = {
@@ -100,26 +99,18 @@ auto keyStateToIcons(const Json::Value& config)
     return key_icon_states;
   }
 
-  bool found_any = false;
+  const auto& format_icons = config["format-icons"];
   for (const auto& key : std::vector<std::string>{"numlock", "capslock", "scrolllock"}) {
     std::string map_key = key.substr(0, key.length() - 4);
     map_key[0] = std::toupper(map_key[0]);
-    if (config["format-icons"].isObject() && config["format-icons"][key].isObject()) {
-      std::string unlocked = config["format-icons"][key]["unlocked"].isString()
-                                 ? config["format-icons"][key]["unlocked"].asString()
-                                 : "unlocked";
-      std::string locked = config["format-icons"][key]["locked"].isString()
-                               ? config["format-icons"][key]["locked"].asString()
-                               : "locked";
-      key_icon_states[map_key] = {unlocked, locked};
-      found_any = true;
+    std::string unlocked = "unlocked";
+    std::string locked = "locked";
+    if (format_icons.isObject() && format_icons[key].isObject()) {
+      const auto& obj = format_icons[key];
+      if (obj["unlocked"].isString()) unlocked = obj["unlocked"].asString();
+      if (obj["locked"].isString()) locked = obj["locked"].asString();
     }
-  }
-
-  if (!found_any) {
-    key_icon_states["Num"] = default_icons;
-    key_icon_states["Caps"] = default_icons;
-    key_icon_states["Scroll"] = default_icons;
+    key_icon_states[map_key] = {unlocked, locked};
   }
 
   return key_icon_states;