chore: scaffold aura workspace and wire the skills dev-cycle

Cargo workspace aura-core -> aura-engine -> aura-cli (bin `aura`) plus nodes/ for hot-reloadable cdylib node crates. Crate bodies are intentionally API-free; types arrive from the first spec. Adds the skills profile (.claude/dev-cycle-profile.yml), the project CLAUDE.md with the eight domain invariants, and the design-ledger skeleton.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Cargo.lock

@@ -0,0 +1,21 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "aura-cli"
+version = "0.1.0"
+dependencies = [
+ "aura-engine",
+]
+
+[[package]]
+name = "aura-core"
+version = "0.1.0"
+
+[[package]]
+name = "aura-engine"
+version = "0.1.0"
+dependencies = [
+ "aura-core",
+]