Fix bugs, remove duplication, and clean up code quality issues

- Log swallowed JSON unmarshal errors in stats and LSP handlers
- Fix debug log file handle leak in tmuxedit (return closer from initDebugLog)
- Check f.Close() errors on write paths in promptstore and tmuxedit
- Fix cacheGet TOCTOU race by using single write lock
- Fix readInput to use passed stdin reader instead of os.Stdin.Stat()
- Remove 45 'moved to' comment tombstones from lsp/handlers.go
- Deduplicate canonicalProvider wrappers (use llmutils.CanonicalProvider directly)
- Remove SetWindow side effect from stats.TakeSnapshot (pure read now)
- Move duplicated splitLines to textutil.SplitLinesBytes
- Collapse StatusSink.SetGlobal 10 params into GlobalStatus struct
- Simplify LRU touchLocked to in-place delete-and-append

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 21 insertions, 6 deletions

diff --git a/internal/hexaicli/run.go b/internal/hexaicli/run.go
index 806f824..9c7ba73 100644
--- a/internal/hexaicli/run.go
+++ b/internal/hexaicli/run.go
@@ -55,7 +55,7 @@ func buildCLIJobs(cfg appconfig.App) ([]cliJob, error) {
 		if provider == "" {
 			provider = cfg.Provider
 		}
-		provider = canonicalProvider(provider)
+		provider = llmutils.CanonicalProvider(provider)
 		derived := llmutils.ConfigForProvider(cfg, provider, entry.Model)
 		req := buildCLIRequest(entry, provider, derived)
 		jobs = append(jobs, cliJob{index: i, provider: provider, entry: entry, cfg: derived, req: req})
@@ -92,10 +92,6 @@ func cliTemperatureFromEntry(cfg appconfig.App, provider string, entry appconfig
 	return llmutils.ResolveTemperature(provider, model, entry.Temperature, cfg.CodingTemperature)
 }
 
-func canonicalProvider(name string) string {
-	return llmutils.CanonicalProvider(name)
-}
-
 // Run executes the Hexai CLI behavior given arguments and I/O streams.
 // It assumes flags have already been parsed by the caller.
 func Run(ctx context.Context, args []string, stdin io.Reader, stdout, stderr io.Writer) error {
@@ -461,10 +457,29 @@ func filterJobsBySelection(jobs []cliJob, indices []int) ([]cliJob, error) {
 	return filtered, nil
 }
 
+// stater is the subset of *os.File needed to detect piped vs terminal input.
+type stater interface {
+	Stat() (os.FileInfo, error)
+}
+
+// isPipedInput reports whether stdin is a pipe or file (not a terminal).
+// For *os.File it checks the file mode; for any other io.Reader it
+// optimistically returns true since non-file readers are typically
+// in-memory buffers used in tests.
+func isPipedInput(stdin io.Reader) bool {
+	if f, ok := stdin.(stater); ok {
+		fi, err := f.Stat()
+		return err == nil && (fi.Mode()&os.ModeCharDevice) == 0
+	}
+	// Non-file readers (e.g. strings.NewReader in tests) always have data.
+	return true
+}
+
 // readInput reads from stdin and args, then combines them per CLI rules.
+// It uses the passed stdin reader (not os.Stdin) to detect piped input.
 func readInput(stdin io.Reader, args []string) (string, error) {
 	var stdinData string
-	if fi, err := os.Stdin.Stat(); err == nil && (fi.Mode()&os.ModeCharDevice) == 0 {
+	if isPipedInput(stdin) {
 		data, readErr := io.ReadAll(stdin)
 		if readErr != nil {
 			return "", fmt.Errorf("hexai: failed to read stdin: %w", readErr)