feat(rag): connect bp_compliance_ce vector corpus to SDK

- Switch LegalRAGClient from empty bp_legal_corpus to bp_compliance_ce
  collection (3,734 chunks across 14 regulations)
- Replace embedding-service (384-dim MiniLM) with Ollama bge-m3 (1024-dim)
- Add standalone RAG search endpoint: POST /sdk/v1/rag/search
- Add regulations list endpoint: GET /sdk/v1/rag/regulations
- Add QDRANT_HOST/PORT env vars to docker-compose.yml
- Update regulation ID mapping to match actual Qdrant payload schema
- Update determineRelevantRegulations for CE corpus regulation IDs

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ai-compliance-sdk/internal/api/handlers/rag_handlers.go

@@ -0,0 +1,76 @@
+package handlers
+
+import (
+	"net/http"
+
+	"github.com/breakpilot/ai-compliance-sdk/internal/ucca"
+	"github.com/gin-gonic/gin"
+)
+
+// RAGHandlers handles RAG search API endpoints.
+type RAGHandlers struct {
+	ragClient *ucca.LegalRAGClient
+}
+
+// NewRAGHandlers creates new RAG handlers.
+func NewRAGHandlers() *RAGHandlers {
+	return &RAGHandlers{
+		ragClient: ucca.NewLegalRAGClient(),
+	}
+}
+
+// SearchRequest represents a RAG search request.
+type SearchRequest struct {
+	Query       string   `json:"query" binding:"required"`
+	Regulations []string `json:"regulations,omitempty"`
+	TopK        int      `json:"top_k,omitempty"`
+}
+
+// Search performs a semantic search across the compliance regulation corpus.
+// POST /sdk/v1/rag/search
+func (h *RAGHandlers) Search(c *gin.Context) {
+	var req SearchRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	if req.TopK <= 0 || req.TopK > 20 {
+		req.TopK = 5
+	}
+
+	results, err := h.ragClient.Search(c.Request.Context(), req.Query, req.Regulations, req.TopK)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "RAG search failed: " + err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{
+		"query":   req.Query,
+		"results": results,
+		"count":   len(results),
+	})
+}
+
+// ListRegulations returns the list of available regulations in the corpus.
+// GET /sdk/v1/rag/regulations
+func (h *RAGHandlers) ListRegulations(c *gin.Context) {
+	regs := h.ragClient.ListAvailableRegulations()
+
+	// Optionally filter by category
+	category := c.Query("category")
+	if category != "" {
+		filtered := make([]ucca.CERegulationInfo, 0)
+		for _, r := range regs {
+			if r.Category == category {
+				filtered = append(filtered, r)
+			}
+		}
+		regs = filtered
+	}
+
+	c.JSON(http.StatusOK, gin.H{
+		"regulations": regs,
+		"count":       len(regs),
+	})
+}