fix(dream-cli): route log() and warn() to stderr

dream benchmark captures cmd_chat's stdout to measure LLM
response timing. Because log() wrote to stdout, the
'[dream] Sending to <model>...' info line emitted inside
cmd_chat leaked into the captured response string.

Appending >&2 to log() and warn() routes their informational
output to stderr, which is also where Unix convention puts
non-data messages. The only $(cmd_*) capture in the file
(cmd_benchmark line 1174) already uses 2>/dev/null, so the
log banner is now cleanly discarded before display.

Minimal 2-line scope. Other helpers (success, error,
log_warn) left on stdout per explicit scope decision.

Author: yasinBursali

dream-server/dream-cli

@@ -42,9 +42,9 @@ NC='\033[0m'
 #=============================================================================
 # Helpers
 #=============================================================================
-log() { echo -e "${CYAN}[dream]${NC} $1"; }
+log() { echo -e "${CYAN}[dream]${NC} $1" >&2; }
 success() { echo -e "${GREEN}✓${NC} $1"; }
-warn() { echo -e "${YELLOW}⚠${NC} $1"; }
+warn() { echo -e "${YELLOW}⚠${NC} $1" >&2; }
 error() { echo -e "${RED}✗${NC} $1"; exit 1; }
 log_warn() { echo -e "${YELLOW}⚠${NC} $1"; }
 log_error() { echo -e "${RED}✗${NC} $1" >&2; }