Docker test fixes: directory pattern matching, mtime-based sync, Go version

- Fixed directory pattern matching: go-gitignore doesn't match 'build/'
  against bare 'build', now checks with trailing slash appended
- Added ModTime to FileMeta for reliable change detection (same-size
  file modifications now sync correctly)
- Updated Dockerfile to golang:1.24-alpine (was 1.22)
- Downgraded go.mod to Go 1.24 (system has custom 1.26.4 build)

Docker tested with podman:
- Initial sync correctly excludes ignored dirs/files
- Nested .gitignore works (sub/ ignores *.tmp)
- Watcher syncs new/modified/deleted files
- Case-sensitive rename (Foo→foo) handled correctly
- Same-size file modifications sync correctly

5 files changed, 12 insertions, 7 deletions

diff --git a/Dockerfile b/Dockerfile
index eb516c2..1258531 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.22-alpine AS builder
+FROM golang:1.24-alpine AS builder
 WORKDIR /src
 COPY go.mod go.sum ./
 RUN go mod download
diff --git a/gitignore.go b/gitignore.go
index 569e191..2c9fc4b 100644
--- a/gitignore.go
+++ b/gitignore.go
@@ -50,8 +50,8 @@ func (s *GitignoreStack) IsIgnored(relPath string) bool {
 			continue
 		}
 
-		posMatch := layer.posRules != nil && layer.posRules.MatchesPath(childRel)
-		negMatch := layer.negRules != nil && layer.negRules.MatchesPath(childRel)
+		posMatch := layer.posRules != nil && (layer.posRules.MatchesPath(childRel) || layer.posRules.MatchesPath(childRel+"/"))
+		negMatch := layer.negRules != nil && (layer.negRules.MatchesPath(childRel) || layer.negRules.MatchesPath(childRel+"/"))
 
 		if negMatch {
 			result = false
diff --git a/go.mod b/go.mod
index 0c8474f..78e7d9a 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module sourcewatch
 
-go 1.26.4
+go 1.24
 
 require (
 	github.com/fsnotify/fsnotify v1.10.1
diff --git a/sync.go b/sync.go
index 526e143..6bdd651 100644
--- a/sync.go
+++ b/sync.go
@@ -5,11 +5,13 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"time"
 )
 
 type FileMeta struct {
 	Size    int64
 	Mode    os.FileMode
+	ModTime time.Time
 	Symlink string
 }
 
@@ -65,6 +67,7 @@ func initialSync(hostDir, dataDir string, stack *GitignoreStack, dryRun bool) (*
 		meta := FileMeta{
 			Size:    info.Size(),
 			Mode:    info.Mode(),
+			ModTime: info.ModTime(),
 			Symlink: linkTarget,
 		}
 		manifest.Files[relPath] = meta
diff --git a/watcher.go b/watcher.go
index 2067887..192b61b 100644
--- a/watcher.go
+++ b/watcher.go
@@ -127,6 +127,7 @@ func syncCreate(srcPath, destPath, relPath string, manifest *Manifest, stack *Gi
 	meta := FileMeta{
 		Size:    info.Size(),
 		Mode:    info.Mode(),
+		ModTime: info.ModTime(),
 		Symlink: linkTarget,
 	}
 	manifest.Files[relPath] = meta
@@ -161,13 +162,14 @@ func syncWrite(srcPath, destPath, relPath string, manifest *Manifest, dryRun, ve
 	}
 
 	meta, exists := manifest.Files[relPath]
-	if exists && meta.Size == info.Size() && meta.Mode == info.Mode() {
+	if exists && meta.Size == info.Size() && meta.Mode == info.Mode() && meta.ModTime.Equal(info.ModTime()) {
 		return
 	}
 
 	manifest.Files[relPath] = FileMeta{
-		Size: info.Size(),
-		Mode: info.Mode(),
+		Size:    info.Size(),
+		Mode:    info.Mode(),
+		ModTime: info.ModTime(),
 	}
 
 	if dryRun {