Converted Descriptor heap to memory arena. Used Gemini with antigravity.

Heap pool code is a mess right now (lot of useless comments)
Will revisit later.

.agent/rules/coding-guidelines.md

@@ -7,4 +7,7 @@ Use [[nodiscard]]
 auto is allowed but when its a pointer add the * and when reference adds the &
 Member variable are CamelCase
 Types are CamelCase
-Functions are CamelCase.
+Functions are CamelCase.
+Add Assert to make sure all assumptions are good. Parameters of functions for example should be verified with Assert.
+Code should be self commented using proper variable names, types and functions. No need to add comments most of the time, unless the algorithm is very complex and hard to read.
+When creating a new system framework, make a unit test. To make the unit test we should not modify the framework code for special unit test case.