Update golangci-lint to v2.12.2 with canonical config (#62)

Updates golangci-lint to v2.12.2 everywhere it is pinned and installs the canonical `.golangci.yml`, then remediates every finding the new linter/config surfaces so `make check` is green.

## Version bump

- `Dockerfile` lint stage: `golangci/golangci-lint:v2.11.3-alpine` -> `v2.12.2-alpine` (digest-pinned, date comment updated)
- `Makefile` `deps` target: `go install` moved from the old v1 module path at `@latest` to the pinned `github.com/golangci/golangci-lint/v2/cmd/golangci-lint@v2.12.2`
- `.golangci.yml` replaced with the canonical config (v2 schema; settings under `linters.settings` so the thresholds actually apply; `default: all` with the standard six disables)
- `script/bootstrap` installs golangci-lint via the system package manager and carries no version pin, so it is unchanged
- CI (`.gitea/workflows/check.yml`) only runs `script/cibuild`, so it needed no change

## Lint remediation

The canonical config surfaced ~3,300 findings across 56k lines. All are fixed, behavior-preserving; incorporates and supersedes the per-package mechanical passes already merged to `main` (refs #61). Highlights:

- `err113`: dynamic errors replaced with package sentinels + `%w` wrapping; comparisons via `errors.Is`
- `goprintffuncname`: printf-style helpers renamed with an `f` suffix (`ui.Writer` message methods, `cli.ReportErrorf`, `database.Fatalf`) and all call sites updated
- `revive` stutter renames: `blob.Handler`, `blob.WithReader`, `blob.ChunkPosition`, `storage.URL`, `storage.Info`; missing doc comments added
- `contextcheck`/`noctx`: `context.Context` threaded through `blob.Packer` and the scanner call sites; context-aware `exec`/`sql` variants
- `funlen`/`cyclop`/`gocognit`/`dupl`: oversized and duplicated functions split into focused helpers (production and test code)
- tests: `t.Parallel()` added where safe (global logger init kept in the serial phase for `-race`), `t.TempDir()`/`t.Helper()` adopted, several suites converted to external test packages
- `gosec`: bounded integer conversions, `ReadHeaderTimeout` on the test HTTP server; remaining warnings suppressed per-site with justifications
- remaining `nolint` directives are rare, targeted, and each carries a reason (e.g. `nilnil` not-found contract in the repository layer, fx module globals, on-disk snake_case struct tags)
- removed the deprecated `log.LogOptions` alias (callers migrated to `log.Options`)

`make check` (tests with `-race`, lint, fmt-check) passes.

Co-authored-by: sneak <sneak@sneak.berlin>
Reviewed-on: #62
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

internal/storage/file.go

@@ -42,18 +42,19 @@ func (f *FileStorer) SetFilesystem(fs afero.Fs) {
 	f.fs = fs
 }
 
-// fullPath returns the full filesystem path for a key.
-func (f *FileStorer) fullPath(key string) string {
-	return filepath.Join(f.basePath, key)
-}
+// storageDirPerm is the mode used for directories created under the
+// storage base path.
+const storageDirPerm = 0o755
 
 // Put stores data at the specified key.
-func (f *FileStorer) Put(ctx context.Context, key string, data io.Reader) error {
+func (f *FileStorer) Put(_ context.Context, key string, data io.Reader) error {
 	path := f.fullPath(key)
 
 	// Create parent directories
 	dir := filepath.Dir(path)
-	if err := f.fs.MkdirAll(dir, 0755); err != nil {
+
+	err := f.fs.MkdirAll(dir, storageDirPerm)
+	if err != nil {
 		return fmt.Errorf("creating directories: %w", err)
 	}
 
@@ -72,12 +73,17 @@ func (f *FileStorer) Put(ctx context.Context, key string, data io.Reader) error
 }
 
 // PutWithProgress stores data with progress reporting.
-func (f *FileStorer) PutWithProgress(ctx context.Context, key string, data io.Reader, size int64, progress ProgressCallback) error {
+func (f *FileStorer) PutWithProgress(
+	_ context.Context, key string, data io.Reader,
+	_ int64, progress ProgressCallback,
+) error {
 	path := f.fullPath(key)
 
 	// Create parent directories
 	dir := filepath.Dir(path)
-	if err := f.fs.MkdirAll(dir, 0755); err != nil {
+
+	err := f.fs.MkdirAll(dir, storageDirPerm)
+	if err != nil {
 		return fmt.Errorf("creating directories: %w", err)
 	}
 
@@ -102,7 +108,7 @@ func (f *FileStorer) PutWithProgress(ctx context.Context, key string, data io.Re
 }
 
 // Get retrieves data from the specified key.
-func (f *FileStorer) Get(ctx context.Context, key string) (io.ReadCloser, error) {
+func (f *FileStorer) Get(_ context.Context, key string) (io.ReadCloser, error) {
 	path := f.fullPath(key)
 
 	file, err := f.fs.Open(path)
@@ -118,7 +124,7 @@ func (f *FileStorer) Get(ctx context.Context, key string) (io.ReadCloser, error)
 }
 
 // Stat returns metadata about an object without retrieving its contents.
-func (f *FileStorer) Stat(ctx context.Context, key string) (*ObjectInfo, error) {
+func (f *FileStorer) Stat(_ context.Context, key string) (*ObjectInfo, error) {
 	path := f.fullPath(key)
 
 	info, err := f.fs.Stat(path)
@@ -137,7 +143,7 @@ func (f *FileStorer) Stat(ctx context.Context, key string) (*ObjectInfo, error)
 }
 
 // Delete removes an object.
-func (f *FileStorer) Delete(ctx context.Context, key string) error {
+func (f *FileStorer) Delete(_ context.Context, key string) error {
 	path := f.fullPath(key)
 
 	err := f.fs.Remove(path)
@@ -233,7 +239,7 @@ func (f *FileStorer) ListStream(ctx context.Context, prefix string) <-chan Objec
 			if err != nil {
 				ch <- ObjectInfo{Err: err}
 
-				return nil // Continue walking despite errors
+				return nil //nolint:nilerr // continue walking despite errors
 			}
 
 			if !info.IsDir() {
@@ -259,13 +265,18 @@ func (f *FileStorer) ListStream(ctx context.Context, prefix string) <-chan Objec
 }
 
 // Info returns human-readable storage location information.
-func (f *FileStorer) Info() StorageInfo {
-	return StorageInfo{
-		Type:     "file",
+func (f *FileStorer) Info() Info {
+	return Info{
+		Type:     schemeFile,
 		Location: f.basePath,
 	}
 }
 
+// fullPath returns the full filesystem path for a key.
+func (f *FileStorer) fullPath(key string) string {
+	return filepath.Join(f.basePath, key)
+}
+
 // progressWriter wraps an io.Writer to track write progress.
 type progressWriter struct {
 	writer   io.Writer