feat: lifetime elision, tooling CI, registry, and LSP locals

Ship the QUALITY_PLAN stretch from ownership through ecosystem: C.1
lifetime elision (bootstrap + selfhost), bux fmt/test/doc CI hooks,
stdlib goldens, package registry (bux search/add), and LSP 0.4
position-sensitive locals with inferred let types. Full-tree format
pass plus Map/Set remove double-free fix.

tests/golden/strings/src/Main.bux

@@ -5,30 +5,30 @@ import Std::String::{String_Len, String_Eq, String_Concat};
 func Main() -> int {
     let hello: String = "Hello";
     let world: String = "World";
-    
+
     PrintLine("String operations:");
-    
+
     // Length
     PrintLine("Length of 'Hello':");
     PrintInt(String_Len(hello));
     PrintLine("");
-    
+
     // Concatenation
     let greeting: String = String_Concat(hello, ", ");
     let greeting2: String = String_Concat(greeting, world);
     let full: String = String_Concat(greeting2, "!");
-    
+
     PrintLine("Concatenated:");
     PrintLine(full);
-    
+
     // Equality
     if String_Eq(hello, "Hello") {
         PrintLine("'Hello' equals 'Hello'");
     }
-    
+
     if !String_Eq(hello, world) {
         PrintLine("'Hello' does not equal 'World'");
     }
-    
+
     return 0;
 }