Four targeted refactors from the automated semantic clustering analysis of 896 functions across 23 packages.

Changes

• server/session.go → server/system_tools.go: Move sysListServersHandler out of the session lifecycle file. It has no session-management logic — it validates a session exists then delegates to callAndLogSysTool, which belongs alongside the SysServer type and registration helpers it works with.

• strutil consolidation: Delete session_suffix.go (1 fn) and json_clone.go (1 fn); merge SessionSuffix and DeepCloneJSON into strutil.go where the other general-purpose helpers live.

• Single source of truth for integrity validation: Export config.ValidateAndNormalizeIntegrityField (was unexported validateAndNormalizeIntegrityField) and remove the near-duplicate invalidIntegrityFieldError + inline NormalizeIntegrityLevel call from guard/wasm_validate.go. Guard now delegates entirely to config:

  // Before (guard/wasm_validate.go)
  func validateIntegrityField(fieldName string, raw interface{}) error {
      s, ok := raw.(string)
      if !ok { return invalidIntegrityFieldError(fieldName) }  // pipe-separated format
      if _, err := config.NormalizeIntegrityLevel(s, false); err == nil { return nil }
      return invalidIntegrityFieldError(fieldName)
  }
  
  // After
  func validateIntegrityField(fieldName string, raw interface{}) error {
      s, _ := raw.(string)  // empty string fails validation for non-string input
      _, err := config.ValidateAndNormalizeIntegrityField(fieldName, s, false)
      return err
  }

  Error message format unified to "<field> must be one of: none, unapproved, approved, merged". Affected tests updated accordingly.

• logger/doc.go: Add explanation of why per-type setup*/handleError* functions are intentional rather than collapsed — each logger type has unique initialization behaviour (e.g. JSONLLogger has no fallback, ToolsLogger closes its file immediately after opening).