Allow setting alpha value for ignorezero layer rule (#2477)

* rename ignorezero to ignorealpha

* allow setting ignorealpha value

This commit allows setting a float value (0-1) for the ignorealpha layer rule.
Does not yet have error handling; invalid ignorealpha layer rule will crash Hyprland.

* add brackets i forgot to add

* prevent crash with invalid ignorealpha value

prevents hyprland from immediately crashing with invalid ignorealpha layer rule
does not log

* don't try to set ignoreAlphaValue if alpha value not specified

* add catch to try, reintroduce ignorezero

- added catch after try cuz i was an idiot
- re-add ignorezero as an alternative to ignorealpha to not introduce a breaking change

* add logging for failed ignorealpha layer rule

* fix get ignorealpha's get VALUE

* check npos and use empty()

* rename VALUE cuz no longer const

* format Shader.hpp

src/config/ConfigManager.cpp

@@ -863,7 +863,7 @@ bool windowRuleValid(const std::string& RULE) {
 }
 
 bool layerRuleValid(const std::string& RULE) {
-    return !(RULE != "noanim" && RULE != "blur" && RULE != "ignorezero");
+    return !(RULE != "noanim" && RULE != "blur" && RULE.find("ignorealpha") != 0 && RULE.find("ignorezero") != 0);
 }
 
 void CConfigManager::handleWindowRule(const std::string& command, const std::string& value) {