Handle errors based on intent: make operations idempotent for known conflicts, and explicitly classify/propagate errors for known transient conditions.

Apply this standard in test scripts and helper utilities:

Example patterns:

# Known conflict: make restore idempotent
catch {r restore key 0 $crafted replace} err

# Known transient cluster routing: ignore MOVED/ASK, fail fast otherwise
if {$cluster_load == 1} {
    if {[catch {$r read} err]} {
        if {[string match {MOVED*} $err] || [string match {ASK*} $err]} {
            continue
        }
        error $err
    }
} else {
    $r read
}