Chapters 1 & 2: Enhanced formatting a little, some paragraph ordering and expressiveness of two sentences.

Add a single paragraph of background information about "Why upgrading Sony's Android before flashing SailfishOS?", plus sone minor fixes.

Many updated links, added Xperia 10 III, updated devices section in chapter 1.

Accumulated sufficient changes that a new point release was overdue.

Deliberately diverging from the frozen version at TJC by introducing Gitlab-specific markup, introducing new information related to the Xperia 10 II, etc., and ultimately defining this as the canonical source (i.e., the "reference version").
Hence this guide earns a new minor release number: 1.2.0 (from 1.1.8)