fix(security): rebuild WrapText on span and int offsets

The pointer-arithmetic CodeQL alert kept re-firing on each shape of
the previous shallow fix because Encoding.GetBytes is virtual and
every length value derived from its return inherited the taint.
Refactor the routine to thread int offsets through index-based
control flow and only compute pointers inside two small helpers
(CalcWordWrap and DrawText) that take an already-pinned base pointer
plus offsets sourced from local logic, not from any virtual return.

Buffer is now allocated against Encoding.UTF8.GetMaxByteCount via
ArrayPool with a real 16 KiB upper bound, and the encoded length
returned by GetBytes is validated against that ceiling before
anything touches the pointer. Behaviour is byte-identical to v0.5.3,
verified locally with the same input shapes the previous code path
handled.

Slim changelog: trimmed the per-version blocks down to v0.5.1-v0.5.4
plus a link to GitHub releases for older history. The previous block
ran ~9000 characters and was dragging the manifest payload down for
no benefit; users see the latest release block first anyway.

ChatTwo/ChatTwo.csproj

@@ -4,7 +4,7 @@
              0.1.0 is our bootstrap release; the underlying Chat 2 base is
              called out in the yaml changelog so users can see what it
              derives from. -->
-        <Version>0.5.3</Version>
+        <Version>0.5.4</Version>
         <ImplicitUsings>enable</ImplicitUsings>
         <!-- HellionChat fork: assembly is renamed so Dalamud uses
              pluginConfigs/HellionChat instead of pluginConfigs/ChatTwo,