fix(restore): add context validity checks to debug cancellation issues

Added explicit context checks at critical points:
1. After extraction completes - logs error if context was cancelled
2. Before database restore loop starts - catches premature cancellation

This helps diagnose issues where all database restores fail with
'context cancelled' even though extraction completed successfully.

The user reported this happening after 4h20m extraction - all 6 DBs
showed 'restore skipped (context cancelled)'. These checks will log
exactly when/where the context becomes invalid.

bin/README.md

@@ -4,8 +4,8 @@ This directory contains pre-compiled binaries for the DB Backup Tool across mult
 
 ## Build Information
 - **Version**: 3.42.50
-- **Build Time**: 2026-01-16_15:09:21_UTC
-- **Git Commit**: dd7c4da
+- **Build Time**: 2026-01-16_17:31:38_UTC
+- **Git Commit**: 698b8a7
 
 ## Recent Updates (v1.1.0)
 - ✅ Fixed TUI progress display with line-by-line output

internal/restore/engine.go

@@ -910,6 +910,16 @@ func (e *Engine) RestoreCluster(ctx context.Context, archivePath string) error {
 		return fmt.Errorf("failed to extract archive: %w", err)
 	}
 
+	// Check context validity after extraction (debugging context cancellation issues)
+	if ctx.Err() != nil {
+		e.log.Error("Context cancelled after extraction - this should not happen",
+			"context_error", ctx.Err(),
+			"extraction_completed", true)
+		operation.Fail("Context cancelled unexpectedly")
+		return fmt.Errorf("context cancelled after extraction completed: %w", ctx.Err())
+	}
+	e.log.Info("Extraction completed, context still valid")
+
 	// Check if user has superuser privileges (required for ownership restoration)
 	e.progress.Update("Checking privileges...")
 	isSuperuser, err := e.checkSuperuser(ctx)
@@ -1108,6 +1118,18 @@ func (e *Engine) RestoreCluster(ctx context.Context, archivePath string) error {
 	var successCount, failCount int32
 	var mu sync.Mutex // Protect shared resources (progress, logger)
 
+	// CRITICAL: Check context before starting database restore loop
+	// This helps debug issues where context gets cancelled between extraction and restore
+	if ctx.Err() != nil {
+		e.log.Error("Context cancelled before database restore loop started",
+			"context_error", ctx.Err(),
+			"total_databases", totalDBs,
+			"parallelism", parallelism)
+		operation.Fail("Context cancelled before database restores could start")
+		return fmt.Errorf("context cancelled before database restore: %w", ctx.Err())
+	}
+	e.log.Info("Starting database restore loop", "databases", totalDBs, "parallelism", parallelism)
+
 	// Timing tracking for restore phase progress
 	restorePhaseStart := time.Now()
 	var completedDBTimes []time.Duration // Track duration for each completed DB restore