Enhance code quality and testing infrastructure

Code improvements:
- Remove unused ErrNotImplemented variable and github.com/pkg/errors dependency
- Add comprehensive package-level documentation
- Fix comment punctuation for consistency (Chtimes, Chown)

Testing:
- Add comprehensive test suite covering all filesystem methods
- Tests for: Mkdir, MkdirAll, OpenFile, Open, Remove, RemoveAll, Stat, Chmod, Chtimes, Chown
- Edge case coverage including error conditions

Repository management:
- Add Dependabot configuration for automated dependency updates
- Add CODEOWNERS file for PR review assignments

Author: claude

.github/CODEOWNERS

@@ -0,0 +1,11 @@
+# Code owners for httpfs repository
+# These owners will be automatically requested for review when someone opens a pull request.
+
+# Default owners for everything in the repo
+* @absfs/maintainers
+
+# Go source code
+*.go @absfs/maintainers
+
+# CI/CD workflows
+.github/ @absfs/maintainers

.github/dependabot.yml

@@ -0,0 +1,21 @@
+version: 2
+updates:
+  # Enable version updates for Go modules
+  - package-ecosystem: "gomod"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 10
+    labels:
+      - "dependencies"
+      - "go"
+
+  # Enable version updates for GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 5
+    labels:
+      - "dependencies"
+      - "github-actions"

go.mod

@@ -5,7 +5,6 @@ go 1.23
 require (
 	github.com/absfs/absfs v0.0.0-20251109181304-77e2f9ac4448
 	github.com/absfs/memfs v0.0.0-20251122223403-0826c6ce3884
-	github.com/pkg/errors v0.9.1
 )
 
 require github.com/absfs/inode v0.0.0-20190804195220-b7cd14cdd0dc // indirect

go.sum

@@ -14,8 +14,6 @@ github.com/mattn/go-colorable v0.1.8 h1:c1ghPdyEDarC70ftn0y+A/Ee++9zz8ljHG1b13eJ
 github.com/mattn/go-colorable v0.1.8/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
-github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
-github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/xtgo/set v1.0.0 h1:6BCNBRv3ORNDQ7fyoJXRv+tstJz3m1JVFQErfeZz2pY=
 github.com/xtgo/set v1.0.0/go.mod h1:d3NHzGzSa0NmB2NhFyECA+QdRp29oEn2xbT+TpeFoM8=
 golang.org/x/sys v0.1.0 h1:kunALQeHf1/185U1i0GOB/fy1IPRDDpuoOOqRReG57U=

httpfs.go

@@ -1,3 +1,7 @@
+// Package httpfs implements a net/http FileSystem interface compatible
+// wrapper around absfs.Filer that supports both read and write operations.
+// It bridges the gap between the absfs filesystem abstraction and Go's
+// standard http.FileServer.
 package httpfs
 
 import (
@@ -7,13 +11,9 @@ import (
 	"strings"
 	"time"
 
-	"github.com/pkg/errors"
-
 	"github.com/absfs/absfs"
 )
 
-var ErrNotImplemented = errors.New("not implemented")
-
 type Httpfs struct {
 	fs absfs.Filer
 }
@@ -112,12 +112,12 @@ func (filer *Httpfs) Chmod(name string, mode os.FileMode) error {
 	return filer.fs.Chmod(name, mode)
 }
 
-// Chtimes changes the access and modification times of the named file
+// Chtimes changes the access and modification times of the named file.
 func (filer *Httpfs) Chtimes(name string, atime time.Time, mtime time.Time) error {
 	return filer.fs.Chtimes(name, atime, mtime)
 }
 
-// Chown changes the owner and group ids of the named file
+// Chown changes the owner and group ids of the named file.
 func (filer *Httpfs) Chown(name string, uid, gid int) error {
 	return filer.fs.Chown(name, uid, gid)
 }