chore: align codebase with bible engineering contracts

- identifier-normalization: use strings.EqualFold in h3c/parser.go
- import-export: CSV now uses UTF-8 BOM and semicolon delimiter
- go-code-style: translate all Russian source strings to English (ADL-007)
- go-background-tasks: add Type, Message, Result fields to Job struct
- go-api: wrap list endpoints in {items, total_count, page, per_page, total_pages}
- module-structure: rename helpers.go → context_sleep.go
- build-version-display: htmlError renders version footer on error pages
- go-logging: migrate all log.Printf calls to log/slog with structured attrs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/collector/redfish_logentries.go

@@ -2,7 +2,7 @@ package collector
 
 import (
 	"context"
-	"log"
+	"log/slog"
 	"net/http"
 	"strings"
 	"time"
@@ -62,7 +62,7 @@ func (c *RedfishConnector) collectRedfishLogEntries(ctx context.Context, client
 	}
 
 	if len(out) > 0 {
-		log.Printf("redfish: collected %d hardware log entries (Systems+Managers SEL, window=7d)", len(out))
+		slog.Info("redfish: collected hardware log entries", "count", len(out), "window", "7d")
 	}
 	return out
 }