C++: Undo increasing query precision.

Author: geoffw0

cpp/ql/src/Likely Bugs/Underspecified Functions/ImplicitFunctionDeclaration.ql

@@ -5,7 +5,7 @@
  * may lead to unpredictable behavior.
  * @kind problem
  * @problem.severity warning
- * @precision high
+ * @precision medium
  * @id cpp/implicit-function-declaration
  * @tags correctness
  *       maintainability

cpp/ql/src/change-notes/2026-03-23-implicit-function-declaration.md

@@ -1,5 +1,4 @@
 ---
 category: minorAnalysis
 ---
-* The "Implicit function declaration" (`cpp/implicit-function-declaration`) query has been promoted to `@precision high`.
 * The "Implicit function declaration" (`cpp/implicit-function-declaration`) query no longer produces results on `build mode: none` databases. These results were found to be very noisy and fundamentally imprecise in this mode.