cimery Sprint 1 — Rust 워크스페이스 + 전 계층 파이프라인

8개 크레이트 구현, cargo test 32개 전부 통과:
- core: Mm/M 단위 newtype, UnitExt 리터럴, FeatureError
- ir: GirderIR + 전 단면 파라미터(PSC-I/U/SteelBox/PlateI) serde JSON
- dsl: Girder builder + 검증 (경간 범위·count·spacing)
- kernel: GeomKernel trait + StubKernel (box mesh, AABB)
- incremental: dirty-tracking IncrementalDb (salsa 업그레이드 경로 주석)
- evaluator: 상태 없는 IR→kernel 브리지
- usd: USDA 1.0 텍스트 익스포트 (CimeryBridgeAPI·GirderAPI schema)
- viewer: wgpu 22 + winit 0.30 컬러 삼각형 (Sprint 1 proof-of-concept)

Sprint 2 다음 단계:
- opencascade-rs로 StubKernel 교체 (실제 PSC-I sweep)
- viewer에서 Girder Mesh 렌더 + 카메라 orbit

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cimery/crates/ir/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name    = "cimery-ir"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+cimery-core = { workspace = true }
+serde       = { workspace = true }
+serde_json  = { workspace = true }
+uuid        = { workspace = true }

cimery/crates/ir/src/lib.rs

@@ -0,0 +1,185 @@
+//! cimery-ir — deterministic intermediate representation.
+//!
+//! Rules:
+//! - Structural values stored as raw `f64` in **mm**.
+//! - Alignment values stored as raw `f64` in **m**.
+//! - Fully serializable: JSON ↔ IR round-trip is lossless.
+//! - Serde field ordering is deterministic (struct field declaration order).
+
+use cimery_core::{MaterialGrade, SectionType};
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+// ─── Feature identity ─────────────────────────────────────────────────────────
+
+/// Stable identifier for a Feature instance across changes.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct FeatureId(pub Uuid);
+
+impl FeatureId {
+    pub fn new() -> Self { Self(Uuid::new_v4()) }
+}
+
+impl Default for FeatureId {
+    fn default() -> Self { Self::new() }
+}
+
+impl std::fmt::Display for FeatureId {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
+// ─── Girder IR ────────────────────────────────────────────────────────────────
+
+/// Fully-resolved Girder specification ready for geometry kernel invocation.
+///
+/// All values are raw primitives — no unit types here (kernel doesn't need them).
+/// Convention: linear = metres, structural = millimetres.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct GirderIR {
+    pub id:                    FeatureId,
+    /// Station along alignment [m].
+    pub station_start:         f64,
+    /// Station along alignment [m].
+    pub station_end:           f64,
+    /// Lateral offset from alignment centreline [mm]. Positive = left.
+    pub offset_from_alignment: f64,
+    pub section_type:          SectionType,
+    pub section:               SectionParams,
+    /// Number of girders placed side by side.
+    pub count:                 u32,
+    /// Centre-to-centre spacing between girders [mm].
+    pub spacing:               f64,
+    pub material:              MaterialGrade,
+}
+
+impl GirderIR {
+    /// Span length in metres.
+    pub fn span_m(&self) -> f64 { self.station_end - self.station_start }
+    /// Span length in millimetres.
+    pub fn span_mm(&self) -> f64 { self.span_m() * 1_000.0 }
+}
+
+// ─── Section params ───────────────────────────────────────────────────────────
+
+/// Cross-section geometry. Tag is the section type name.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(tag = "kind")]
+pub enum SectionParams {
+    PscI(PscISectionParams),
+    PscU(PscUSectionParams),
+    SteelBox(SteelBoxParams),
+    SteelPlateI(SteelPlateIParams),
+}
+
+/// PSC I-girder section dimensions [all mm].
+///
+/// #[param(unit="mm", range=1200..=3000, default=1800)] total_height
+/// #[param(unit="mm", range=400..=800,   default=600)]  top_flange_width
+/// #[param(unit="mm", range=100..=300,   default=150)]  top_flange_thickness
+/// #[param(unit="mm", range=400..=900,   default=700)]  bottom_flange_width
+/// #[param(unit="mm", range=120..=300,   default=180)]  bottom_flange_thickness
+/// #[param(unit="mm", range=150..=350,   default=200)]  web_thickness
+/// #[param(unit="mm", range=0..=100,     default=50)]   haunch
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PscISectionParams {
+    pub total_height:           f64,
+    pub top_flange_width:       f64,
+    pub top_flange_thickness:   f64,
+    pub bottom_flange_width:    f64,
+    pub bottom_flange_thickness:f64,
+    pub web_thickness:          f64,
+    pub haunch:                 f64,
+}
+
+impl PscISectionParams {
+    /// Korean KDS standard I-girder, 40 m span.
+    pub fn kds_standard() -> Self {
+        Self {
+            total_height:            1800.0,
+            top_flange_width:         600.0,
+            top_flange_thickness:     150.0,
+            bottom_flange_width:      700.0,
+            bottom_flange_thickness:  180.0,
+            web_thickness:            200.0,
+            haunch:                    50.0,
+        }
+    }
+}
+
+/// PSC U-girder section [all mm].
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PscUSectionParams {
+    pub total_height:   f64,
+    pub top_width:      f64,
+    pub bottom_width:   f64,
+    pub web_thickness:  f64,
+    pub flange_thickness: f64,
+}
+
+/// Steel box girder section [all mm].
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SteelBoxParams {
+    pub total_height:           f64,
+    pub top_width:              f64,
+    pub bottom_width:           f64,
+    pub web_thickness:          f64,
+    pub top_flange_thickness:   f64,
+    pub bottom_flange_thickness:f64,
+}
+
+/// Steel plate I-girder section [all mm].
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SteelPlateIParams {
+    pub total_height:     f64,
+    pub flange_width:     f64,
+    pub flange_thickness: f64,
+    pub web_thickness:    f64,
+}
+
+// ─── Tests ────────────────────────────────────────────────────────────────────
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use cimery_core::{MaterialGrade, SectionType};
+
+    pub fn sample_girder() -> GirderIR {
+        GirderIR {
+            id:                    FeatureId::new(),
+            station_start:         100.0,
+            station_end:           140.0,
+            offset_from_alignment: 0.0,
+            section_type:          SectionType::PscI,
+            section:               SectionParams::PscI(PscISectionParams::kds_standard()),
+            count:                 5,
+            spacing:               2500.0,
+            material:              MaterialGrade::C50,
+        }
+    }
+
+    #[test]
+    fn span_lengths() {
+        let g = sample_girder();
+        assert!((g.span_m()  - 40.0).abs()     < f64::EPSILON);
+        assert!((g.span_mm() - 40_000.0).abs() < f64::EPSILON);
+    }
+
+    #[test]
+    fn json_roundtrip() {
+        let g    = sample_girder();
+        let json = serde_json::to_string_pretty(&g).unwrap();
+        let g2: GirderIR = serde_json::from_str(&json).unwrap();
+        assert!((g.span_m() - g2.span_m()).abs() < f64::EPSILON);
+        assert_eq!(g.count, g2.count);
+        assert_eq!(g.section_type, g2.section_type);
+    }
+
+    #[test]
+    fn feature_id_is_unique() {
+        let a = FeatureId::new();
+        let b = FeatureId::new();
+        assert_ne!(a, b);
+    }
+}