feat: Implement Read tool for file system access (#16)

Implements the Read tool feature requested in issue #14.

## Features Implemented

- ✅ Tool for reading files from the filesystem
- ✅ File path argument support
- ✅ Line range functionality for selective reading
- ✅ Performance-optimized buffered file reading
- ✅ Comprehensive parameter validation
- ✅ Both text and JSON output formats
- ✅ Example usage through tool parameter definitions

## Technical Details

Adds a new `Read` tool to the LLM tool system with:

- `file_path`: Required parameter for file to read
- `start_line`, `end_line`: Optional line range parameters (1-indexed)
- `format`: Output format (text or json)

Integrates with existing file service infrastructure and follows
established patterns.

Closes #14

Generated with [Claude Code](https://claude.ai/code)

---------

Signed-off-by: Eden Reich <[email protected]>
Co-authored-by: claude[bot] <209825114+claude[bot]@users.noreply.github.com>
Co-authored-by: Eden Reich <[email protected]>

Author: edenreich

CLAUDE.md

@@ -10,6 +10,8 @@ This is the Inference Gateway CLI (`infer`), a Go-based command-line tool for ma
 
 **Note: All commands should be run with `flox activate -- <command>` to ensure the proper development environment is activated.**
 
+**IMPORTANT: Always run `task setup` first when working with a fresh checkout of the repository to ensure all dependencies are properly installed.**
+
 ### Setup Development Environment
 ```bash
 flox activate -- task setup

internal/container/container.go

@@ -48,43 +48,35 @@ func NewServiceContainer(cfg *config.Config) *ServiceContainer {
 
 // initializeDomainServices creates and wires domain service implementations
 func (c *ServiceContainer) initializeDomainServices() {
-	// Create conversation repository
 	c.conversationRepo = services.NewInMemoryConversationRepository()
 
-	// Create model service
 	c.modelService = services.NewHTTPModelService(
 		c.config.Gateway.URL,
 		c.config.Gateway.APIKey,
 	)
 
-	// Create tool service first (needed by chat service)
+	c.fileService = services.NewLocalFileService()
+
 	if c.config.Tools.Enabled {
-		c.toolService = services.NewLLMToolService(c.config)
+		c.toolService = services.NewLLMToolService(c.config, c.fileService)
 	} else {
 		c.toolService = services.NewNoOpToolService()
 	}
 
-	// Create chat service with tool service
 	c.chatService = services.NewStreamingChatService(
 		c.config.Gateway.URL,
 		c.config.Gateway.APIKey,
 		c.config.Gateway.Timeout,
 		c.toolService,
 	)
-
-	// Create file service
-	c.fileService = services.NewLocalFileService()
 }
 
 // initializeUIComponents creates UI components and theme
 func (c *ServiceContainer) initializeUIComponents() {
-	// Create theme based on configuration
 	c.theme = ui.NewDefaultTheme()
 
-	// Create layout manager
 	c.layout = ui.NewDefaultLayout()
 
-	// Create component factory
 	c.componentFactory = ui.NewComponentFactory(c.theme, c.layout, c.modelService)
 }
 

internal/domain/interfaces.go

@@ -103,6 +103,7 @@ type ToolService interface {
 type FileService interface {
 	ListProjectFiles() ([]string, error)
 	ReadFile(path string) (string, error)
+	ReadFileLines(path string, startLine, endLine int) (string, error)
 	ValidateFile(path string) error
 	GetFileInfo(path string) (FileInfo, error)
 }

internal/services/file.go

@@ -1,6 +1,7 @@
 package services
 
 import (
+	"bufio"
 	"fmt"
 	"io/fs"
 	"os"
@@ -161,6 +162,46 @@ func (s *LocalFileService) ReadFile(path string) (string, error) {
 	return string(content), nil
 }
 
+func (s *LocalFileService) ReadFileLines(path string, startLine, endLine int) (string, error) {
+	if err := s.ValidateFile(path); err != nil {
+		return "", err
+	}
+
+	file, err := os.Open(path)
+	if err != nil {
+		return "", fmt.Errorf("failed to open file: %w", err)
+	}
+	defer func() {
+		_ = file.Close()
+	}()
+
+	scanner := bufio.NewScanner(file)
+	var result strings.Builder
+	currentLine := 1
+
+	for scanner.Scan() {
+		if startLine > 0 && currentLine < startLine {
+			currentLine++
+			continue
+		}
+		if endLine > 0 && currentLine > endLine {
+			break
+		}
+
+		if result.Len() > 0 {
+			result.WriteString("\n")
+		}
+		result.WriteString(scanner.Text())
+		currentLine++
+	}
+
+	if err := scanner.Err(); err != nil {
+		return "", fmt.Errorf("failed to read file lines: %w", err)
+	}
+
+	return result.String(), nil
+}
+
 func (s *LocalFileService) ValidateFile(path string) error {
 	if path == "" {
 		return fmt.Errorf("file path cannot be empty")