feat: migrate embeddings to Candle WASM + remove semantic type inference

Major architectural changes:

1. EMBEDDINGS ENGINE (ONNX → Candle WASM):
   - Replace ONNX Runtime with Rust Candle compiled to WASM
   - Embedded model in WASM binary (no external downloads)
   - Quantized Q8 precision with <50MB memory footprint
   - Zero-download, offline-first operation
   - Same embedding quality (all-MiniLM-L6-v2)

2. REMOVE SEMANTIC TYPE INFERENCE:
   - Delete embeddedKeywordEmbeddings.ts (14MB of pre-computed embeddings)
   - Remove typeAwareQueryPlanner.ts and semanticTypeInference.ts
   - Remove VerbExactMatchSignal (uses keyword embeddings)
   - Update SmartRelationshipExtractor to 3 signals (55%/30%/15% weights)

API CHANGES (requires v7.0.0):
- Removed: inferTypes(), inferNouns(), inferVerbs(), inferIntent()
- Removed: getSemanticTypeInference(), SemanticTypeInference class
- Removed: TypeInference, SemanticTypeInferenceOptions types

Users can still use natural language queries in find() - they just
need to specify type explicitly for type-optimized searches.

PACKAGE SIZE IMPACT:
- Compressed: 90.1 MB → 86.2 MB (-4.3%)
- Uncompressed: 114.4 MB → 100.3 MB (-12%)
- ~448K lines of code removed

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/build-candle-wasm.sh

@@ -0,0 +1,132 @@
+#!/bin/bash
+# Build script for Candle WASM embedding engine
+#
+# Requirements:
+# - Rust toolchain (rustup)
+# - wasm-pack (cargo install wasm-pack)
+# - Build tools (build-essential on Ubuntu/Debian)
+#
+# Usage:
+#   ./scripts/build-candle-wasm.sh
+#   ./scripts/build-candle-wasm.sh --release
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+CANDLE_DIR="$PROJECT_ROOT/src/embeddings/candle-wasm"
+OUTPUT_DIR="$PROJECT_ROOT/src/embeddings/wasm/pkg"
+
+# Colors for output
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m' # No Color
+
+echo -e "${GREEN}Building Candle WASM embedding engine...${NC}"
+
+# Check prerequisites
+check_prerequisites() {
+    local missing=()
+
+    if ! command -v rustc &> /dev/null; then
+        missing+=("rust (install via: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh)")
+    fi
+
+    if ! command -v wasm-pack &> /dev/null; then
+        missing+=("wasm-pack (install via: cargo install wasm-pack)")
+    fi
+
+    if ! command -v cc &> /dev/null && ! command -v gcc &> /dev/null; then
+        missing+=("C compiler (install via: sudo apt-get install build-essential)")
+    fi
+
+    if [ ${#missing[@]} -gt 0 ]; then
+        echo -e "${RED}Missing prerequisites:${NC}"
+        for prereq in "${missing[@]}"; do
+            echo "  - $prereq"
+        done
+        exit 1
+    fi
+
+    echo -e "${GREEN}All prerequisites found.${NC}"
+}
+
+# Download model files if not present
+download_model() {
+    local MODEL_DIR="$PROJECT_ROOT/assets/models/all-MiniLM-L6-v2"
+    local SAFETENSORS="$MODEL_DIR/model.safetensors"
+    local TOKENIZER="$MODEL_DIR/tokenizer.json"
+    local CONFIG="$MODEL_DIR/config.json"
+
+    if [ -f "$SAFETENSORS" ] && [ -f "$TOKENIZER" ] && [ -f "$CONFIG" ]; then
+        echo -e "${GREEN}Model files already present.${NC}"
+        return
+    fi
+
+    echo -e "${YELLOW}Downloading model files...${NC}"
+    mkdir -p "$MODEL_DIR"
+
+    # Download from HuggingFace Hub
+    local HF_URL="https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2/resolve/main"
+
+    if [ ! -f "$SAFETENSORS" ]; then
+        curl -L "$HF_URL/model.safetensors" -o "$SAFETENSORS"
+    fi
+
+    if [ ! -f "$TOKENIZER" ]; then
+        curl -L "$HF_URL/tokenizer.json" -o "$TOKENIZER"
+    fi
+
+    if [ ! -f "$CONFIG" ]; then
+        curl -L "$HF_URL/config.json" -o "$CONFIG"
+    fi
+
+    echo -e "${GREEN}Model files downloaded.${NC}"
+}
+
+# Build WASM
+build_wasm() {
+    local BUILD_MODE="${1:-release}"
+
+    echo -e "${GREEN}Building WASM (${BUILD_MODE})...${NC}"
+    cd "$CANDLE_DIR"
+
+    if [ "$BUILD_MODE" = "release" ]; then
+        wasm-pack build --target web --release --out-dir "$OUTPUT_DIR"
+    else
+        wasm-pack build --target web --dev --out-dir "$OUTPUT_DIR"
+    fi
+
+    echo -e "${GREEN}WASM build complete. Output: $OUTPUT_DIR${NC}"
+}
+
+# Main
+main() {
+    local mode="release"
+
+    while [[ $# -gt 0 ]]; do
+        case $1 in
+            --dev|--debug)
+                mode="dev"
+                shift
+                ;;
+            --release)
+                mode="release"
+                shift
+                ;;
+            *)
+                echo "Unknown option: $1"
+                exit 1
+                ;;
+        esac
+    done
+
+    check_prerequisites
+    download_model
+    build_wasm "$mode"
+
+    echo -e "${GREEN}Done! WASM package ready at: $OUTPUT_DIR${NC}"
+}
+
+main "$@"