refactor(extract): move text extraction to internal/textextract

KTD1 third step: material parsing returns to its own capability.
- ExtractTextWithAnchors + docx/anchor helpers move from squad/extract.go
  to internal/textextract (pure stdlib, no workflowdef dep)
- squad/extract.go keeps only ExtractAdvisorBriefing (squad domain logic)
- callers updated: squad context builders, bizdev materials, server
  chat_document_reader, materialindex pipeline
- reverse dependency materialindex -> squad eliminated (KTD1 explicit goal)
- module-boundaries.yaml: textextract declared + 4 edges
- verified: build/vet clean, arch green, textextract/squad/materialindex/
  bizdev tests green; server pre-existing env-dependent failure unchanged
  (issue #2, fails with and without this change)

internal/bizdev/materials.go

@@ -12,6 +12,7 @@ import (
 
 	"chat-agent-system/internal/materialindex"
 	"chat-agent-system/internal/squad"
+	"chat-agent-system/internal/textextract"
 	"chat-agent-system/internal/storage"
 )
 
@@ -154,7 +155,7 @@ func (s *Service) materialToItems(
 			meta["parse_engine"] = "mineru"
 		}
 	} else {
-		text, err = squad.ExtractTextWithAnchors(fileName, data)
+		text, err = textextract.ExtractTextWithAnchors(fileName, data)
 		if err != nil {
 			return nil, nil, fmt.Errorf("extract material %q: %w", fileName, err)
 		}

internal/materialindex/pipeline.go

@@ -18,7 +18,7 @@ import (
 	"chat-agent-system/internal/config"
 	"chat-agent-system/internal/kb"
 	"chat-agent-system/internal/mineru"
-	"chat-agent-system/internal/squad"
+	"chat-agent-system/internal/textextract"
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
@@ -233,7 +233,7 @@ func (p *Pipeline) ResetForReparse(ctx context.Context, blobSHA string) bool {
 // fallback text from squad.ExtractTextWithAnchors (may be empty).
 func (p *Pipeline) EnsureParsed(ctx context.Context, fileName string, blobSHA string, data []byte) (markdown string, fromMinerU bool, err error) {
 	fallback := func() (string, bool, error) {
-		txt, e := squad.ExtractTextWithAnchors(fileName, data)
+		txt, e := textextract.ExtractTextWithAnchors(fileName, data)
 		return strings.TrimSpace(txt), false, e
 	}
 	if p == nil {

internal/server/chat_document_reader.go

@@ -15,7 +15,7 @@ import (
 	"chat-agent-system/internal/docgov"
 	"chat-agent-system/internal/intent"
 	"chat-agent-system/internal/projectinstance"
-	"chat-agent-system/internal/squad"
+	"chat-agent-system/internal/textextract"
 	"chat-agent-system/internal/storage"
 	"chat-agent-system/internal/stream"
 	"chat-agent-system/internal/workflowscope"
@@ -179,7 +179,7 @@ func (s *Server) resolveLatestUploadDocument(ctx context.Context, projectID int6
 		}
 		markdown = strings.TrimSpace(md)
 	} else {
-		md, extractErr := squad.ExtractTextWithAnchors(ref.FileName, data)
+		md, extractErr := textextract.ExtractTextWithAnchors(ref.FileName, data)
 		if extractErr != nil {
 			return nil, extractErr
 		}

internal/squad/context.go

@@ -1,6 +1,7 @@
 package squad
 
 import (
+	"chat-agent-system/internal/textextract"
 	"encoding/json"
 	"fmt"
 	"os"
@@ -145,7 +146,7 @@ func (cm *ContextManager) InjectMaterials(wsDir string, materials []MaterialItem
 			name = "material.txt"
 		}
 
-		textContent, err := ExtractTextWithAnchors(name, m.Content)
+		textContent, err := textextract.ExtractTextWithAnchors(name, m.Content)
 		if err != nil || strings.TrimSpace(textContent) == "" {
 			textContent = string(m.Content)
 		}

internal/squad/extract.go

@@ -1,183 +1,12 @@
 package squad
 
 import (
-	"archive/zip"
-	"bytes"
-	"encoding/xml"
 	"fmt"
-	"io"
-	"path/filepath"
 	"strings"
-	"unicode/utf8"
 
 	"chat-agent-system/internal/workflowdef"
 )
 
-// ExtractTextWithAnchors 从不同格式材料中提取纯文本，并自动注入物理页码锚点 <!-- page N -->
-func ExtractTextWithAnchors(filename string, data []byte) (string, error) {
-	if len(data) == 0 {
-		return "", nil
-	}
-
-	ext := strings.ToLower(filepath.Ext(filename))
-	switch ext {
-	case ".txt", ".md", ".json", ".yaml", ".yml":
-		return string(data), nil
-	case ".docx":
-		txt, err := extractTextFromDOCX(data)
-		if err == nil && len(strings.TrimSpace(txt)) > 0 {
-			return injectPageAnchorsForText(txt), nil
-		}
-		// 降级：从二进制中提取可见字符
-		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
-	default:
-		// 通用降级
-		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
-	}
-}
-
-// injectPageAnchorsForText 将连续文本按约 1200 字符切分，并注入 <!-- page N --> 锚点
-func injectPageAnchorsForText(raw string) string {
-	raw = strings.TrimSpace(raw)
-	if raw == "" {
-		return ""
-	}
-
-	// 若原始文本中包含换页符 \f
-	if strings.Contains(raw, "\f") {
-		pages := strings.Split(raw, "\f")
-		var sb strings.Builder
-		for i, page := range pages {
-			pTrim := strings.TrimSpace(page)
-			if pTrim == "" {
-				continue
-			}
-			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n%s\n", i+1, pTrim))
-		}
-		return strings.TrimSpace(sb.String())
-	}
-
-	// 否则按段落累加约 1200 字符为一页
-	paragraphs := strings.Split(raw, "\n")
-	var sb strings.Builder
-	currentPage := 1
-	currentLen := 0
-
-	sb.WriteString(fmt.Sprintf("<!-- page %d -->\n", currentPage))
-	for _, p := range paragraphs {
-		pTrim := strings.TrimRight(p, "\r\t ")
-		pLen := utf8.RuneCountInString(pTrim)
-		if currentLen > 0 && currentLen+pLen > 1200 {
-			currentPage++
-			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n", currentPage))
-			currentLen = 0
-		}
-		sb.WriteString(pTrim)
-		sb.WriteString("\n")
-		currentLen += pLen + 1
-	}
-
-	return strings.TrimSpace(sb.String())
-}
-
-// extractTextFromDOCX 解析 docx 的 word/document.xml 提取段落文本
-func extractTextFromDOCX(data []byte) (string, error) {
-	r, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
-	if err != nil {
-		return "", err
-	}
-
-	var docFile *zip.File
-	for _, f := range r.File {
-		if f.Name == "word/document.xml" {
-			docFile = f
-			break
-		}
-	}
-	if docFile == nil {
-		return "", fmt.Errorf("word/document.xml not found in docx")
-	}
-
-	rc, err := docFile.Open()
-	if err != nil {
-		return "", err
-	}
-	defer rc.Close()
-
-	xmlBytes, err := io.ReadAll(rc)
-	if err != nil {
-		return "", err
-	}
-
-	decoder := xml.NewDecoder(bytes.NewReader(xmlBytes))
-	var sb strings.Builder
-	inParagraph := false
-
-	for {
-		tok, err := decoder.Token()
-		if err != nil {
-			break
-		}
-		switch elem := tok.(type) {
-		case xml.StartElement:
-			if elem.Name.Local == "p" {
-				inParagraph = true
-			} else if elem.Name.Local == "br" {
-				for _, attr := range elem.Attr {
-					if attr.Name.Local == "type" && attr.Value == "page" {
-						sb.WriteString("\f")
-					}
-				}
-			} else if elem.Name.Local == "lastRenderedPageBreak" {
-				sb.WriteString("\f")
-			}
-		case xml.EndElement:
-			if elem.Name.Local == "p" {
-				if inParagraph {
-					sb.WriteString("\n")
-					inParagraph = false
-				}
-			}
-		case xml.CharData:
-			sb.Write(elem)
-		}
-	}
-
-	return sb.String(), nil
-}
-
-// extractAsciiUtf8Strings 降级算法：从二进制流中提取连续的有效可读 UTF-8 文本
-func extractAsciiUtf8Strings(data []byte) string {
-	var sb strings.Builder
-	var cur bytes.Buffer
-
-	flush := func() {
-		if cur.Len() >= 4 {
-			s := cur.String()
-			s = strings.TrimSpace(s)
-			if s != "" {
-				sb.WriteString(s)
-				sb.WriteString("\n")
-			}
-		}
-		cur.Reset()
-	}
-
-	for i := 0; i < len(data); {
-		r, size := utf8.DecodeRune(data[i:])
-		if size > 0 && r != utf8.RuneError && (r >= 32 || r == '\n' || r == '\t' || r == '\r') {
-			cur.WriteRune(r)
-			i += size
-		} else {
-			flush()
-			i++
-		}
-	}
-	flush()
-
-	return sb.String()
-}
-
 // ExtractAdvisorBriefing 从 output.md 与黑板事实中提取 B 轨业务参谋决策锦囊
 func ExtractAdvisorBriefing(taskKey string, markdownBody string, fields map[string]string) *AdvisorBriefing {
 	if fields == nil {

internal/squad/workspace_context_build.go

@@ -1,6 +1,7 @@
 package squad
 
 import (
+	"chat-agent-system/internal/textextract"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -68,7 +69,7 @@ func (e *WorkspaceEngine) buildContextSystem(workDir string, req WorkspacePrepar
 			}
 
 			// 自动提取纯文本并注入页码锚点 <!-- page N -->
-			textContent, err := ExtractTextWithAnchors(name, m.Content)
+			textContent, err := textextract.ExtractTextWithAnchors(name, m.Content)
 			if err != nil || strings.TrimSpace(textContent) == "" {
 				textContent = string(m.Content)
 			}

internal/textextract/extract.go

@@ -0,0 +1,178 @@
+package textextract
+
+import (
+	"archive/zip"
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"path/filepath"
+	"strings"
+	"unicode/utf8"
+
+)
+
+// ExtractTextWithAnchors 从不同格式材料中提取纯文本，并自动注入物理页码锚点 <!-- page N -->
+func ExtractTextWithAnchors(filename string, data []byte) (string, error) {
+	if len(data) == 0 {
+		return "", nil
+	}
+
+	ext := strings.ToLower(filepath.Ext(filename))
+	switch ext {
+	case ".txt", ".md", ".json", ".yaml", ".yml":
+		return string(data), nil
+	case ".docx":
+		txt, err := extractTextFromDOCX(data)
+		if err == nil && len(strings.TrimSpace(txt)) > 0 {
+			return injectPageAnchorsForText(txt), nil
+		}
+		// 降级：从二进制中提取可见字符
+		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
+	default:
+		// 通用降级
+		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
+	}
+}
+
+// injectPageAnchorsForText 将连续文本按约 1200 字符切分，并注入 <!-- page N --> 锚点
+func injectPageAnchorsForText(raw string) string {
+	raw = strings.TrimSpace(raw)
+	if raw == "" {
+		return ""
+	}
+
+	// 若原始文本中包含换页符 \f
+	if strings.Contains(raw, "\f") {
+		pages := strings.Split(raw, "\f")
+		var sb strings.Builder
+		for i, page := range pages {
+			pTrim := strings.TrimSpace(page)
+			if pTrim == "" {
+				continue
+			}
+			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n%s\n", i+1, pTrim))
+		}
+		return strings.TrimSpace(sb.String())
+	}
+
+	// 否则按段落累加约 1200 字符为一页
+	paragraphs := strings.Split(raw, "\n")
+	var sb strings.Builder
+	currentPage := 1
+	currentLen := 0
+
+	sb.WriteString(fmt.Sprintf("<!-- page %d -->\n", currentPage))
+	for _, p := range paragraphs {
+		pTrim := strings.TrimRight(p, "\r\t ")
+		pLen := utf8.RuneCountInString(pTrim)
+		if currentLen > 0 && currentLen+pLen > 1200 {
+			currentPage++
+			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n", currentPage))
+			currentLen = 0
+		}
+		sb.WriteString(pTrim)
+		sb.WriteString("\n")
+		currentLen += pLen + 1
+	}
+
+	return strings.TrimSpace(sb.String())
+}
+
+// extractTextFromDOCX 解析 docx 的 word/document.xml 提取段落文本
+func extractTextFromDOCX(data []byte) (string, error) {
+	r, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
+	if err != nil {
+		return "", err
+	}
+
+	var docFile *zip.File
+	for _, f := range r.File {
+		if f.Name == "word/document.xml" {
+			docFile = f
+			break
+		}
+	}
+	if docFile == nil {
+		return "", fmt.Errorf("word/document.xml not found in docx")
+	}
+
+	rc, err := docFile.Open()
+	if err != nil {
+		return "", err
+	}
+	defer rc.Close()
+
+	xmlBytes, err := io.ReadAll(rc)
+	if err != nil {
+		return "", err
+	}
+
+	decoder := xml.NewDecoder(bytes.NewReader(xmlBytes))
+	var sb strings.Builder
+	inParagraph := false
+
+	for {
+		tok, err := decoder.Token()
+		if err != nil {
+			break
+		}
+		switch elem := tok.(type) {
+		case xml.StartElement:
+			if elem.Name.Local == "p" {
+				inParagraph = true
+			} else if elem.Name.Local == "br" {
+				for _, attr := range elem.Attr {
+					if attr.Name.Local == "type" && attr.Value == "page" {
+						sb.WriteString("\f")
+					}
+				}
+			} else if elem.Name.Local == "lastRenderedPageBreak" {
+				sb.WriteString("\f")
+			}
+		case xml.EndElement:
+			if elem.Name.Local == "p" {
+				if inParagraph {
+					sb.WriteString("\n")
+					inParagraph = false
+				}
+			}
+		case xml.CharData:
+			sb.Write(elem)
+		}
+	}
+
+	return sb.String(), nil
+}
+
+// extractAsciiUtf8Strings 降级算法：从二进制流中提取连续的有效可读 UTF-8 文本
+func extractAsciiUtf8Strings(data []byte) string {
+	var sb strings.Builder
+	var cur bytes.Buffer
+
+	flush := func() {
+		if cur.Len() >= 4 {
+			s := cur.String()
+			s = strings.TrimSpace(s)
+			if s != "" {
+				sb.WriteString(s)
+				sb.WriteString("\n")
+			}
+		}
+		cur.Reset()
+	}
+
+	for i := 0; i < len(data); {
+		r, size := utf8.DecodeRune(data[i:])
+		if size > 0 && r != utf8.RuneError && (r >= 32 || r == '\n' || r == '\t' || r == '\r') {
+			cur.WriteRune(r)
+			i += size
+		} else {
+			flush()
+			i++
+		}
+	}
+	flush()
+
+	return sb.String()
+}