Fix lint errors and restyle Material docs theme

Author: nficano

internal/cache/local.go

@@ -377,7 +377,11 @@ func (lc *LocalCache) withFlock(fn func() error) error {
 	if err := flock(lockFile); err != nil {
 		return fmt.Errorf("acquiring file lock: %w", err)
 	}
-	defer funlock(lockFile)
+	defer func() {
+		if err := funlock(lockFile); err != nil {
+			slog.Warn("failed to release cache file lock", "error", err)
+		}
+	}()
 
 	return fn()
 }

internal/cache/s3.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"log/slog"
 	"strconv"
-	"sync"
 	"sync/atomic"
 	"time"
 
@@ -47,7 +46,6 @@ type S3CacheConfig struct {
 // additional mutex for internal state like hit/miss counters.
 type S3Cache struct {
 	cfg S3CacheConfig
-	mu  sync.Mutex // guards nothing mutable beyond atomic counters; reserved for future use
 
 	hitCount      atomic.Int64
 	missCount     atomic.Int64

internal/cli/register.go

@@ -209,13 +209,6 @@ func splitPath(rawURL string) []string {
 // isAuthError returns true if the error represents a 401 or 403 response
 // from the GitHub API.
 func isAuthError(err error) bool {
-	type statusCoder interface {
-		Error() string
-	}
-	// Check for *github.APIError by inspecting the error chain.
-	type apiErr interface {
-		Error() string
-	}
 	// Walk the error chain looking for an APIError with an auth status code.
 	current := err
 	for current != nil {

internal/runner/manager.go

@@ -23,7 +23,6 @@ import (
 // One Manager runs per process.
 type Manager struct {
 	cfg     *config.Config
-	cfgMu   sync.RWMutex // Protects cfg during hot reload.
 	pools   []*Pool
 	metrics *metrics.Metrics
 	logger  *slog.Logger

mkdocs.yml

@@ -7,21 +7,28 @@ repo_url: https://github.com/nficano/github-runner
 
 theme:
   name: material
+  font:
+    text: IBM Plex Sans
+    code: JetBrains Mono
   palette:
-    - scheme: default
-      primary: deep purple
-      accent: purple
+    - media: "(prefers-color-scheme: light)"
+      scheme: default
+      primary: teal
+      accent: amber
       toggle:
-        icon: material/brightness-7
+        icon: material/weather-night
         name: Switch to dark mode
-    - scheme: slate
-      primary: deep purple
-      accent: purple
+    - media: "(prefers-color-scheme: dark)"
+      scheme: slate
+      primary: cyan
+      accent: lime
       toggle:
-        icon: material/brightness-4
+        icon: material/weather-sunny
         name: Switch to light mode
   features:
     - content.code.copy
+    - navigation.tabs
+    - navigation.instant
     - navigation.sections
     - navigation.expand
     - navigation.top