Remediate all lint findings under the canonical golangci-lint config

Fix every finding surfaced by the canonical .golangci.yml with
golangci-lint v2.12.2 (refs #61), behavior-preserving throughout:

- err113: dynamic errors replaced with package-level sentinels and %w
  wrapping; direct comparisons converted to errors.Is
- goprintffuncname: printf-style helpers renamed with an f suffix
  (ui.Writer message methods, cli.ReportErrorf, database.Fatalf,
  vaultik stdoutf) and all call sites updated
- revive: stuttering type names renamed (blob.Handler, blob.WithReader,
  blob.ChunkPosition, storage.URL, storage.Info), doc comments added,
  unused parameters blanked, package comments added
- contextcheck/noctx: ctx threaded through blob.Packer
  (AddChunk/Flush/FinalizeBlob/PackChunks) and scanner call sites;
  context-aware exec and sql variants used
- funlen/cyclop/gocognit/nestif/dupl: oversized or duplicated
  functions split into focused helpers across production and test code
- paralleltest/tparallel/thelper/usetesting/testpackage: tests
  parallelized where safe (global log.Initialize kept in the serial
  phase), helpers marked, t.TempDir adopted, external test packages
  where only exported API is used
- gosec: integer conversions clamped or justified, header timeouts
  added, remaining findings suppressed with per-site justifications
- mnd/goconst/lll/wsl_v5/nlreturn/noinlineerr/errcheck and other
  mechanical findings fixed directly

Remove the deprecated log.LogOptions alias (callers migrated to
log.Options). make check is green.

internal/storage/storer.go

@@ -30,14 +30,15 @@ type ObjectInfo struct {
 	Err  error  // Error for streaming results (nil on success)
 }
 
-// StorageInfo provides human-readable storage configuration.
-type StorageInfo struct {
+// Info provides human-readable storage configuration.
+type Info struct {
 	Type     string // "s3" or "file"
 	Location string // endpoint/bucket for S3, base path for filesystem
 }
 
 // Storer defines the interface for storage backends.
-// All paths are relative to the storage root (bucket/prefix for S3, base directory for filesystem).
+// All paths are relative to the storage root (bucket/prefix for S3, base
+// directory for filesystem).
 type Storer interface {
 	// Put stores data at the specified key.
 	// Parent directories are created automatically for filesystem backends.
@@ -46,7 +47,8 @@ type Storer interface {
 	// PutWithProgress stores data with progress reporting.
 	// Size must be the exact size of the data to store.
 	// The progress callback is called periodically with bytes transferred.
-	PutWithProgress(ctx context.Context, key string, data io.Reader, size int64, progress ProgressCallback) error
+	PutWithProgress(ctx context.Context, key string, data io.Reader,
+		size int64, progress ProgressCallback) error
 
 	// Get retrieves data from the specified key.
 	// The caller must close the returned ReadCloser.
@@ -70,5 +72,5 @@ type Storer interface {
 	ListStream(ctx context.Context, prefix string) <-chan ObjectInfo
 
 	// Info returns human-readable storage location information.
-	Info() StorageInfo
+	Info() Info
 }