install.sh: offer to install missing tools via dnf

Instead of dying immediately, check_tools now lists missing packages,
asks the user to install them with dnf, and re-verifies after install.
Decline still aborts as before.

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

system_setup/install.sh

@@ -28,11 +28,37 @@ require_root() {
 }
 
 check_tools() {
+    declare -A tool_pkg=(
+        [lsblk]="util-linux"       [blkid]="util-linux"
+        [parted]="parted"          [partprobe]="parted"
+        [mkfs.btrfs]="btrfs-progs" [git]="git"
+        [e2fsck]="e2fsprogs"       [resize2fs]="e2fsprogs"
+        [tune2fs]="e2fsprogs"
+    )
     local missing=()
     for tool in lsblk blkid parted partprobe mkfs.btrfs git e2fsck resize2fs tune2fs; do
         command -v "$tool" >/dev/null 2>&1 || missing+=("$tool")
     done
-    [[ ${#missing[@]} -eq 0 ]] || die "Missing required tools: ${missing[*]}"
+    [[ ${#missing[@]} -eq 0 ]] && return 0
+
+    echo "Missing required tools: ${missing[*]}"
+    local pkgs=()
+    for tool in "${missing[@]}"; do
+        local pkg="${tool_pkg[$tool]}"
+        [[ " ${pkgs[*]} " != *" $pkg "* ]] && pkgs+=("$pkg")
+    done
+
+    read -r -p "  Install missing packages (${pkgs[*]}) with dnf? [y/N]: " ans
+    if [[ "${ans,,}" == "y" ]]; then
+        dnf install -y "${pkgs[@]}" || die "Package installation failed."
+        local still_missing=()
+        for tool in "${missing[@]}"; do
+            command -v "$tool" >/dev/null 2>&1 || still_missing+=("$tool")
+        done
+        [[ ${#still_missing[@]} -eq 0 ]] || die "Still missing after install: ${still_missing[*]}"
+    else
+        die "Missing required tools: ${missing[*]}"
+    fi
 }
 
 # Returns 0 if the remote install.sh matches this script's checksum,