fix(text): no stroke-font tracking after big-font and fallback glyphs (#1470)

Every glyph advanced by the face's letter spacing, including CJK glyphs a
style's big font or the TrueType fallback supplies. Their advances already
carry the gap (big font) or side bearings (TrueType), so with an LFF primary
such as iso each ideograph took 1.33 heights instead of one.
Face::spacing_after(ch) gives the tracking only to glyphs the stroke font
draws itself; every layout path uses it.

The 1.8-height widths in the report were the TEXT bounds estimate counting
UTF-8 bytes; opencadcodec 1109d52 counts characters.

Pins opencadcodec 1109d52, opencadkernel 8a246b0, opencadgraph 3c4af1c.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugins/opencad-python/Cargo.lock

@@ -1265,7 +1265,7 @@ dependencies = [
 [[package]]
 name = "opencadcodec"
 version = "0.5.5"
-source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=7c20aa7#7c20aa7fad405845c5bd5cdcc2a232cdc2a4687d"
+source = "git+https://github.com/HakanSeven12/opencadcodec.git?rev=1109d52#1109d52f65ae8f00d75f43445908bff48807c0c5"
 dependencies = [
  "ahash 0.8.12",
  "anyhow",