feat: publish Dever core with project scaffolding and versioned AI skills

.trellis/tasks/09-29-build-cache-storage/implement.jsonl

@@ -0,0 +1,4 @@
+{"file":".trellis/spec/backend/directory-structure.md","reason":"确认 native build、CLI、测试目录和单一 owner 边界"}
+{"file":".trellis/tasks/09-29-build-cache-storage/research/cache-boundaries.md","reason":"保持 locked/offline 工具链、launcher 与机器共享缓存合同"}
+{"file":".trellis/spec/backend/error-handling.md","reason":"保持临时目录生命周期、原子发布和清理错误合同"}
+{"file":".trellis/spec/backend/quality-guidelines.md","reason":"遵守定向测试与低磁盘验证约束"}