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-backlight-slider.5.scd

@@ -41,6 +41,17 @@ The brightness can be controlled by dragging the slider across the bar or clicki
 	default: false ++
 	Enables this module to consume all left over space dynamically.
 
+*Note*: As well as the JSON configuration, the slider modules are special in
+that they *require* styling to work. You *need* to set *min-width* and/or
+*min-height* (depending on whether your slider is vertical or not) for it to
+display correctly. That is a GTK detail, not an issue with Waybar. See the
+*STYLE* section below.
+
+*Warning*: If *min* is set to *0* (default), the slider can set brightness to
+*0*, which may completely disable the backlight on some devices, making the
+screen fully black. Consider setting a small minimum value (e.g. *10*) or
+configuring brightness keybinds as a fallback.
+
 # EXAMPLES
 
 ```