Fix model selection UI: update descriptions and default to Qwen 3.5

- Option 2 description: "Qwen2.5 · Qwen2.5-Coder" → "Qwen 3.5 (Feb 2026)"
- Default choice: 1 (Western) → 2 (Performance/Qwen 3.5)
- Recommended tier logic: use TOTAL_VRAM and match actual tier names
  (4B/9B/35B/27B for Qwen 3.5, not old 7B/14B/22B/32B)
- Users with 6GB GPUs now see the 4B option marked "fast — fully in VRAM"
  instead of having to pick Custom and type model names manually

https://claude.ai/code/session_01PtYTPherSJaxDEVPgF6Nxu

laptop_full_setup.sh

@@ -466,23 +466,32 @@ if $INSTALL_AI; then
     echo ""
     echo "  Origin preference:"
     echo "  1) Western-only      — Codestral (Mistral 🇫🇷) · Phi4 (Microsoft 🇺🇸) · Mistral 7B"
-    echo "  2) Performance-first — Qwen2.5 · Qwen2.5-Coder (Chinese, top benchmarks)"
-    echo "  3) Mixed             — Western for chat/reasoning, Qwen for coding only"
+    echo "  2) Performance-first — Qwen 3.5 (Feb 2026, top benchmarks, vision+code)"
+    echo "  3) Mixed             — Western for chat, Qwen 3.5 for coding"
     echo "  4) Custom            — enter model names manually"
     echo ""
-    read -rp "  Choice [1]: " MODEL_PREF
-    MODEL_PREF="${MODEL_PREF:-1}"
+    read -rp "  Choice [2]: " MODEL_PREF
+    MODEL_PREF="${MODEL_PREF:-2}"
 
-    # Q4 approximate sizes in GB: 7B=4, 13-15B=9, 22B=13, 32B=19, 70-72B=41
+    # Q4_K_M approximate weights in GB: 4B=2.5, 7B=4, 9B=5.5, 14B=9, 22B=13, 27B=17, 35B-MoE=12, 70B=41
 
     # VRAM-based recommendation (soft — shown as suggestion only)
-    if   [[ "$VRAM_GB" -ge 20 ]]; then REC_TIER="32B"
-    elif [[ "$VRAM_GB" -ge 12 ]]; then REC_TIER="22B"
-    elif [[ "$VRAM_GB" -ge  6 ]]; then REC_TIER="14B"
-    else                                REC_TIER="7B"
-    fi
-    # performance pref has no 22B tier
-    [[ "$MODEL_PREF" == "2" && "$REC_TIER" == "22B" ]] && REC_TIER="32B"
+    case "$MODEL_PREF" in
+        2)  # Performance (Qwen 3.5)
+            if   [[ "$TOTAL_VRAM" -ge 28 ]]; then REC_TIER="27B"
+            elif [[ "$TOTAL_VRAM" -ge 14 ]]; then REC_TIER="35B"
+            elif [[ "$TOTAL_VRAM" -ge  8 ]]; then REC_TIER="9B"
+            else                                   REC_TIER="4B"
+            fi
+            ;;
+        *)  # Western / Mixed
+            if   [[ "$TOTAL_VRAM" -ge 40 ]]; then REC_TIER="70B"
+            elif [[ "$TOTAL_VRAM" -ge 12 ]]; then REC_TIER="35B"
+            elif [[ "$TOTAL_VRAM" -ge  8 ]]; then REC_TIER="14B"
+            else                                   REC_TIER="7B"
+            fi
+            ;;
+    esac
 
     echo ""
     echo "  Size tier — estimated speed on your ${VRAM_GB}GB GPU:"