chore: import clean Agent Desk snapshot (2/7)

internal/ai/rag/chunk/fixed_provider.go

@@ -0,0 +1,44 @@
+package chunk
+
+import (
+	"agent-desk/internal/pkg/enums"
+	"context"
+)
+
+type fixedProvider struct{}
+
+func NewFixedProvider() Provider {
+	return &fixedProvider{}
+}
+
+func (p *fixedProvider) Name() string {
+	return string(enums.KnowledgeChunkProviderFixed)
+}
+
+func (p *fixedProvider) Supports(contentType enums.KnowledgeDocumentContentType) bool {
+	return true
+}
+
+func (p *fixedProvider) Chunk(ctx context.Context, req *ChunkRequest) ([]ChunkResult, error) {
+	text := req.PlainText
+	if text == "" {
+		text = req.Content
+	}
+	parts := splitPlainText(text, req.Options)
+	results := make([]ChunkResult, 0, len(parts))
+	for i, part := range parts {
+		results = append(results, ChunkResult{
+			ChunkNo:     i,
+			Title:       req.DocumentTitle,
+			Content:     part,
+			ChunkType:   enums.KnowledgeChunkTypeText,
+			SectionPath: req.DocumentTitle,
+			CharCount:   len([]rune(part)),
+			TokenCount:  estimateTokenCount(part),
+			Metadata: map[string]any{
+				"provider": enums.KnowledgeChunkProviderFixed,
+			},
+		})
+	}
+	return results, nil
+}