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Add ChrFont, a reader for Gravograph .CHR engraving fonts, plus UI to convert placed text into engraved geometry in the CAD converter. The .CHR files are obfuscated with a single-byte XOR. Different GravoStyle releases use different keys (0x2F in older versions, 0xCF in the 7000 series, and others across the font library), so the key is auto-detected from byte 1 of the file: the font name is ASCII stored as UTF-16LE, so the high byte of its first character is 0x00 in plaintext and the raw byte equals the key. This reads every font in a GravoStyle install regardless of version, not just one hardcoded key. UI: right-clicking a text item in EntityView raises TextConvertRequested; CadConverterForm renders it via ChrFont with H/V alignment and adds the result on an ENGRAVE layer. Tests use Xunit.SkippableFact and a gitignored test-config.json so the suite points at a local .CHR file without committing proprietary assets. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>