docs(man): backfill man pages with wiki-only info (source-of-truth pass)

Port information that previously lived only in the GitHub wiki into the
authoritative scdoc man pages, so the man pages become the single source
of truth for module documentation.

33 man pages enriched (options, format replacements, actions, style
selectors, troubleshooting and implementation notes). Additions were
verified against the source; stale/incorrect wiki entries were
deliberately not ported. All pages still compile with scdoc.

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

man/waybar-pulseaudio-slider.5.scd

@@ -87,6 +87,12 @@ The volume can be controlled by dragging the slider across the bar or clicking o
 
 # STYLE
 
+Unlike most modules, the slider modules *require* styling to display correctly.
+In particular you *need* to set *min-width* and/or *min-height* (depending on
+whether the slider is vertical or horizontal) on the *trough* node, otherwise
+the slider renders too small to be usable. This is a GTK detail, not a Waybar
+issue.
+
 The slider is a component with multiple CSS Nodes, of which the following are exposed:
 
 *#pulseaudio-slider*: ++