Merge branch 'feature/cli-batch' into new

# Conflicts:
#	internal/cmd/dev/cmd_file_sync.go
#	internal/cmd/docs/cmd_sync.go
#	internal/cmd/sdk/generators/go.go
#	internal/cmd/setup/cmd_registry.go
#	pkg/cli/daemon.go
#	pkg/io/local/client.go
#	pkg/io/local/client_test.go
#	pkg/mcp/transport_tcp.go

internal/cmd/dev/cmd_file_sync.go

@@ -15,10 +15,10 @@ import (
 	"strings"
 
 	"github.com/host-uk/core/pkg/cli"
-	"github.com/host-uk/core/pkg/errors"
 	"github.com/host-uk/core/pkg/git"
 	"github.com/host-uk/core/pkg/i18n"
 	coreio "github.com/host-uk/core/pkg/io"
+	"github.com/host-uk/core/pkg/log"
 	"github.com/host-uk/core/pkg/repos"
 )
 
@@ -59,7 +59,7 @@ func runFileSync(source string) error {
 
 	// Security: Reject path traversal attempts
 	if strings.Contains(source, "..") {
-		return errors.E("dev.sync", "path traversal not allowed", nil)
+		return log.E("dev.sync", "path traversal not allowed", nil)
 	}
 
 	// Validate source exists
@@ -82,7 +82,7 @@ func runFileSync(source string) error {
 	// Let's stick to os.Stat for source properties finding as typically allowed for CLI args.
 
 	if err != nil {
-		return errors.E("dev.sync", i18n.T("cmd.dev.file_sync.error.source_not_found", map[string]interface{}{"Path": source}), err)
+		return log.E("dev.sync", i18n.T("cmd.dev.file_sync.error.source_not_found", map[string]interface{}{"Path": source}), err)
 	}
 
 	// Find target repos
@@ -131,7 +131,11 @@ func runFileSync(source string) error {
 			}
 		} else {
 			// Ensure dir exists
-			coreio.Local.EnsureDir(filepath.Dir(destPath))
+			if err := coreio.Local.EnsureDir(filepath.Dir(destPath)); err != nil {
+				cli.Print("  %s %s: copy failed: %s\n", errorStyle.Render("x"), repoName, err)
+				failed++
+				continue
+			}
 			if err := coreio.Copy(coreio.Local, source, coreio.Local, destPath); err != nil {
 				cli.Print("  %s %s: copy failed: %s\n", errorStyle.Render("x"), repoName, err)
 				failed++
@@ -205,12 +209,12 @@ func resolveTargetRepos(pattern string) ([]*repos.Repo, error) {
 	// Load registry
 	registryPath, err := repos.FindRegistry()
 	if err != nil {
-		return nil, errors.E("dev.sync", "failed to find registry", err)
+		return nil, log.E("dev.sync", "failed to find registry", err)
 	}
 
 	registry, err := repos.LoadRegistry(registryPath)
 	if err != nil {
-		return nil, errors.E("dev.sync", "failed to load registry", err)
+		return nil, log.E("dev.sync", "failed to load registry", err)
 	}
 
 	// Match pattern against repo names

internal/cmd/docs/cmd_sync.go

@@ -140,7 +140,10 @@ func runDocsSync(registryPath string, outputDir string, dryRun bool) error {
 			src := filepath.Join(docsDir, f)
 			dst := filepath.Join(repoOutDir, f)
 			// Ensure parent dir
-			io.Local.EnsureDir(filepath.Dir(dst))
+			if err := io.Local.EnsureDir(filepath.Dir(dst)); err != nil {
+				cli.Print("  %s %s: %s\n", errorStyle.Render("✗"), f, err)
+				continue
+			}
 
 			if err := io.Copy(io.Local, src, io.Local, dst); err != nil {
 				cli.Print("  %s %s: %s\n", errorStyle.Render("✗"), f, err)

internal/cmd/sdk/generators/go.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 
 	coreio "github.com/host-uk/core/pkg/io"
+	"github.com/host-uk/core/pkg/log"
 )
 
 // GoGenerator generates Go SDKs from OpenAPI specs.
@@ -37,7 +38,7 @@ func (g *GoGenerator) Install() string {
 // Generate creates SDK from OpenAPI spec.
 func (g *GoGenerator) Generate(ctx context.Context, opts Options) error {
 	if err := coreio.Local.EnsureDir(opts.OutputDir); err != nil {
-		return fmt.Errorf("go.Generate: failed to create output dir: %w", err)
+		return log.E("go.Generate", "failed to create output dir", err)
 	}
 
 	if g.Available() {
@@ -59,7 +60,7 @@ func (g *GoGenerator) generateNative(ctx context.Context, opts Options) error {
 	cmd.Stderr = os.Stderr
 
 	if err := cmd.Run(); err != nil {
-		return fmt.Errorf("go.generateNative: %w", err)
+		return log.E("go.generateNative", "oapi-codegen failed", err)
 	}
 
 	goMod := fmt.Sprintf("module %s\n\ngo 1.21\n", opts.PackageName)

internal/cmd/setup/cmd_registry.go

@@ -117,7 +117,7 @@ func runRegistrySetupWithReg(ctx context.Context, reg *repos.Registry, registryP
 
 			// Check if already exists
 			repoPath := filepath.Join(basePath, repo.Name)
-			// Check .git dir existence via List
+			// Check .git dir existence via Exists
 			if coreio.Local.Exists(filepath.Join(repoPath, ".git")) {
 				exists++
 				continue

pkg/cli/daemon.go

@@ -74,14 +74,13 @@ func IsStderrTTY() bool {
 
 // PIDFile manages a process ID file for single-instance enforcement.
 type PIDFile struct {
-	medium io.Medium
+	path string
-	path   string
+	mu   sync.Mutex
-	mu     sync.Mutex
 }
 
 // NewPIDFile creates a PID file manager.
-func NewPIDFile(m io.Medium, path string) *PIDFile {
+func NewPIDFile(path string) *PIDFile {
-	return &PIDFile{medium: m, path: path}
+	return &PIDFile{path: path}
 }
 
 // Acquire writes the current PID to the file.
@@ -91,7 +90,7 @@ func (p *PIDFile) Acquire() error {
 	defer p.mu.Unlock()
 
 	// Check if PID file exists
-	if data, err := p.medium.Read(p.path); err == nil {
+	if data, err := io.Local.Read(p.path); err == nil {
 		pid, err := strconv.Atoi(data)
 		if err == nil && pid > 0 {
 			// Check if process is still running
@@ -102,19 +101,19 @@ func (p *PIDFile) Acquire() error {
 			}
 		}
 		// Stale PID file, remove it
-		_ = p.medium.Delete(p.path)
+		_ = io.Local.Delete(p.path)
 	}
 
 	// Ensure directory exists
 	if dir := filepath.Dir(p.path); dir != "." {
-		if err := p.medium.EnsureDir(dir); err != nil {
+		if err := io.Local.EnsureDir(dir); err != nil {
 			return fmt.Errorf("failed to create PID directory: %w", err)
 		}
 	}
 
 	// Write current PID
 	pid := os.Getpid()
-	if err := p.medium.Write(p.path, strconv.Itoa(pid)); err != nil {
+	if err := io.Local.Write(p.path, strconv.Itoa(pid)); err != nil {
 		return fmt.Errorf("failed to write PID file: %w", err)
 	}
 
@@ -125,7 +124,7 @@ func (p *PIDFile) Acquire() error {
 func (p *PIDFile) Release() error {
 	p.mu.Lock()
 	defer p.mu.Unlock()
-	return p.medium.Delete(p.path)
+	return io.Local.Delete(p.path)
 }
 
 // Path returns the PID file path.
@@ -219,7 +218,7 @@ func (h *HealthServer) Start() error {
 
 	go func() {
 		if err := h.server.Serve(listener); err != http.ErrServerClosed {
-			LogError("health server error", "err", err)
+			LogError(fmt.Sprintf("health server error: %v", err))
 		}
 	}()
 
@@ -247,10 +246,6 @@ func (h *HealthServer) Addr() string {
 
 // DaemonOptions configures daemon mode execution.
 type DaemonOptions struct {
-	// Medium is the storage backend for PID files.
-	// Defaults to io.Local if not set.
-	Medium io.Medium
-
 	// PIDFile path for single-instance enforcement.
 	// Leave empty to skip PID file management.
 	PIDFile string
@@ -287,9 +282,6 @@ func NewDaemon(opts DaemonOptions) *Daemon {
 	if opts.ShutdownTimeout == 0 {
 		opts.ShutdownTimeout = 30 * time.Second
 	}
-	if opts.Medium == nil {
-		opts.Medium = io.Local
-	}
 
 	d := &Daemon{
 		opts:   opts,
@@ -297,7 +289,7 @@ func NewDaemon(opts DaemonOptions) *Daemon {
 	}
 
 	if opts.PIDFile != "" {
-		d.pid = NewPIDFile(opts.Medium, opts.PIDFile)
+		d.pid = NewPIDFile(opts.PIDFile)
 	}
 
 	if opts.HealthAddr != "" {

pkg/mcp/transport_tcp.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"context"
 	"fmt"
+	"io"
 	"net"
 	"os"
 
@@ -11,6 +12,9 @@ import (
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 )
 
+// maxMCPMessageSize is the maximum size for MCP JSON-RPC messages (10 MB).
+const maxMCPMessageSize = 10 * 1024 * 1024
+
 // TCPTransport manages a TCP listener for MCP.
 type TCPTransport struct {
 	addr     string
@@ -36,6 +40,12 @@ func (s *Service) ServeTCP(ctx context.Context, addr string) error {
 	}
 	defer t.listener.Close()
 
+	// Close listener when context is cancelled to unblock Accept
+	go func() {
+		<-ctx.Done()
+		t.listener.Close()
+	}()
+
 	if addr == "" {
 		addr = t.listener.Addr().String()
 	}
@@ -84,9 +94,11 @@ type connTransport struct {
 }
 
 func (t *connTransport) Connect(ctx context.Context) (mcp.Connection, error) {
+	scanner := bufio.NewScanner(t.conn)
+	scanner.Buffer(make([]byte, 64*1024), maxMCPMessageSize)
 	return &connConnection{
 		conn:    t.conn,
-		scanner: bufio.NewScanner(t.conn),
+		scanner: scanner,
 	}, nil
 }
 
@@ -102,10 +114,8 @@ func (c *connConnection) Read(ctx context.Context) (jsonrpc.Message, error) {
 		if err := c.scanner.Err(); err != nil {
 			return nil, err
 		}
-		// EOF
+		// EOF - connection closed cleanly
-		// Return error to signal closure, as per Scanner contract?
+		return nil, io.EOF
-		// SDK usually expects error on close.
-		return nil, fmt.Errorf("EOF")
 	}
 	line := c.scanner.Bytes()
 	return jsonrpc.DecodeMessage(line)