Add terminology guidance for LoongArch ABI aspects

[Copilot]

The terms "old world"/"new world" and "ABI1.0"/"ABI2.0" are too vague and conflate distinct technical aspects of LoongArch ABI differences.

Changes

Added info boxes to the old-and-new-worlds documentation (Chinese and English) with a reference table distinguishing:

Aspect	Precise term (previously "new world")	Precise term (previously "old world")
Boot protocol	UEFI	BPI
Linux UAPI	5.19 UAPI	"4.19" UAPI¹
Object file ABI	unqualified, or "object file ABI v1" / EF_LARCH_OBJABI_V1	"object file ABI v0"²
Relocation style	unqualified, or "direct-style relocs"	stack-machine-based relocs

¹ Quoted because upstream Linux 4.19.x does not support LoongArch
² No EF_LARCH_OBJABI_V0 flag exists

The boxes appear prominently after the construction warning, guiding authors to use precise terminology in new content while preserving the historical document's existing terms.

Screenshots

Chinese version:

English version:

Original prompt

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This section details on the original issue you should resolve

<issue_title>Migrate to more precise terminology for "old-world and new-world" topics</issue_title>
<issue_description>While being convenient to use, the terms "old world" / "new world" are oftentimes too vague, and this can lead to people conflating different aspects of the problem. The Loongson terms "ABI1.0" / "ABI2.0" are no better choice because the semantics is equivalent to the former, and arguably the mention of "ABI" is worse, because "object file ABI" is already a thing when it comes to ABI differences.

So, we should adopt a new approach where we clearly distinguish the different aspects of LoongArch ABI differences:

Aspect	New term in favor of "new world"	New term in favor of "old world"
Boot protocol	UEFI	BPI
Linux UAPI	(the) 5.19 UAPI	(the) "4.19" UAPI1
Object file ABI	preferably unqualified, "object file ABI v1", or EF_LARCH_OBJABI_V1 if necessary	"object file ABI v0"2
Relocation style	preferably unqualified, "direct-style relocs" if necessary	stack-machine-based relocs

We should add info boxes to remind people to be aware of this, and switch to the new, more precise terminology for newly written material.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Migrate to more precise terminology for "old-world and new-world" topics #438

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Footnotes

1. Quote the "4.19" part whenever possible, because the upstream 4.19.x versions of Linux actually does NOT support LoongArch. ↩

2. There is no EF_LARCH_OBJABI_V0. ↩