v1.0.4

Documentation, lint hardening, and code-quality improvements. No API changes, no behavior changes.

Dependencies

• Bumped github.com/otfabric/go-mms from v1.0.3 → v1.0.4 (documentation and lint hardening; no API or behavior changes).
• Bumped github.com/otfabric/go-cotp (indirect) from v1.0.1 → v1.0.2.

Documentation — error taxonomy covering all 20 sentinel values, 7 typed error structs

(ReferenceError, DecodeError, ModelError, ReportError, SCLParseError,
DataAccessError, ControlError), underlying MMS error passthrough, and errors.Is /
errors.As usage patterns.

• Added link to ERRORS.md in README.md documentation table and repository file-tree section.

Linting and code quality

• golangci-lint exclusion-free (except two documented gocritic disables):
  • Removed blanket errcheck suppression for test files; all issues fixed in code.
  • Removed dead staticcheck SA2002 test-file exclusion (SA2002 does not occur in this repo).
  • ifElseChain disabled: three-branch if/else if/else patterns are preferred over switch
    for exclusive error-then-nil-then-value decisions.
  • exitAfterDefer disabled: Example_* documentation functions intentionally show
    defer client.Close followed by log.Fatal to model correct cleanup for users.
• Fixed unchecked error returns across 10 test files:
  • c.Abort, sub.Close, defer sub.Close → _ = ... or defer func() { _ = ... }()
  • srv.MMS().SetVariableRead(...) → wrapped in if err := ...; err != nil { t.Fatalf(...) }
  • srv.RegisterControl(...) in example_test.go → _ = srv.RegisterControl(...)
• Converted if/else if/else chains in bulk.go and dataset.go to switch statements.
• Fixed exitAfterDefer in all example programs (basic-client, control, files, reports,
  ied-client, ied-server) and scl/cmd/sclgen: moved defer cancel() / defer stop() to
  after the last potential fatal exit; explicit cleanup called before each log.Fatal.
• Removed unused test helper return values:
  • setupRCBLoopback dropped *mms.Server return (never used by any caller).
  • setupWritableLoopback dropped *writableVars return (never used by any caller).
  • executeCmd in scl/cmd/sclparse dropped string return (never used by any caller).
• Added unparam and gocritic linters to .golangci.yml.
• Added vuln target (govulncheck) to Makefile and wired it into make check.

No API changes. No breaking changes.

Import path remains github.com/otfabric/go-iec61850.