stage1: memory/report overhaul

- split util_base.hpp from util.hpp
- new namespaces: `mem` and `heap`
- new `mem::Allocator` interface
- new `heap::CAllocator` impl with global `heap::c_allocator`
- new `heap::ArenaAllocator` impl
- new `mem::TypeInfo` extracts names without RTTI
- name extraction is enabled w/ ZIG_ENABLE_MEM_PROFILE=1
- new `mem::List` takes explicit `Allocator&` parameter
- new `mem::HashMap` takes explicit `Allocator&` parameter
- add Codegen.pass1_arena and use for all `ZigValue` allocs
- deinit Codegen.pass1_arena early in `zig_llvm_emit_output()`

src/tokenizer.cpp

@@ -397,10 +397,10 @@ static void invalid_char_error(Tokenize *t, uint8_t c) {
 void tokenize(Buf *buf, Tokenization *out) {
     Tokenize t = {0};
     t.out = out;
-    t.tokens = out->tokens = allocate<ZigList<Token>>(1);
+    t.tokens = out->tokens = heap::c_allocator.create<ZigList<Token>>();
     t.buf = buf;
 
-    out->line_offsets = allocate<ZigList<size_t>>(1);
+    out->line_offsets = heap::c_allocator.create<ZigList<size_t>>();
     out->line_offsets->append(0);
 
     // Skip the UTF-8 BOM if present