[phase 1] Simplify type prefixes: IE -> I, drop TE/NE/GE prefixes

[aregtech]

Important

Refactoring changes should be rebased and merged against this branch:
feature/655-api-modernization-and-refactoring

Summary

Remove or shorten the legacy Hungarian-style type prefixes used throughout the SDK.

Current prefixes and their purpose

Prefix	Meaning	Example	Count
IE	Interface	IEByteBuffer, IEIOStream, IESyncObject	~12 classes
TE	Template	TEArrayList, TEHashMap, TELinkedList	~14 classes
NE	Namespace (utility)	NECommon, NEString, NEService	~10 classes
GE	Global/Engine	GEGlobal.h, GEMacros.h, GETypes.h	~4 files

Target state

Current	New	Rationale
IEByteBuffer	IByteBuffer	I prefix for interfaces is widely understood
IEIOStream	IIOStream	Same
IESyncObject	ISyncObject	Same
TEArrayList<T>	ArrayList<T>	Templates are obvious from <T> syntax
TEHashMap<K,V>	HashMap<K,V>	Same
TELinkedList<T>	LinkedList<T>	Same
TEString<T>	Keep or rename to BasicString<T>	Follows std::basic_string convention
NECommon	Dissolved into areg::common namespace	Handled by namespace issue
NEString	Dissolved into areg::string namespace	Same
GEGlobal.h	areg/global.h	Drop prefix from filenames
GEMacros.h	areg/macros.h	Same
GETypes.h	areg/types.h	Same
GESwitches.h	areg/switches.h	Same

Depends on

• Namespace issue must be completed first (or done simultaneously), since NE removal requires namespaces to be in place.

Scope

• ~12 interface classes (IE prefix)
• ~14 template classes (TE prefix)
• ~10 namespace utility classes (NE prefix) — covered by namespace issue
• ~4 global header files (GE prefix)
• All files that reference these types (essentially the entire codebase)

Acceptance criteria

• No IE prefix remains — all converted to I
• No TE prefix remains — all dropped
• No GE prefix remains in filenames
• NE classes dissolved into namespaces (coordinated with namespace issue)
• All #include paths updated for renamed files
• Project compiles and all tests pass

[aregtech]

Done in #673