Generate shared narrative assets

[xtraid]

Summary

• define the closed wang-narrative-assets-v1 manifest and generate shared narrative assets for dossier v2 and canonical Pages
• add semantic solver-trace milestone selection, SAT presentation slots, optimized-mechanism frames, and verified square/generalized/hex composites
• keep dossier v1 unchanged while hardening path, hash, toolchain, source, and atomic-install validation

Validation

• make check
• 290 renderer tests
• strict GCC and Clang builds
• sanitizer, analyzer, Memcheck, and Cachegrind
• C coverage: 90.0% lines, 100% functions, 80.0% branches
• Python coverage: 83%
• parser fuzz smoke: 2000 runs
• dossier smoke and Pages checks
• two independent reviews with no remaining findings

Scope

T96 shared narrative assets v1. Merge is intentionally left for a separate review step.