feat(installer): show croc log-send TUI on install error

On any ERR, both installers now trap the failure, log the line/exit
code, and pop a dialog yes/no asking whether to send the log to another
system via croc. Falls back to a plain read prompt if dialog is absent.
Added dialog and croc to packages.extra so they are present in the live ISO.

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

setup/arch-autoinstall.sh

@@ -7,7 +7,7 @@
 # Answerfile fields: drive, kernel, keymap, hostname, username, encrypt, fido2_root,
 #                    fido2_user, run_tui  (password always prompted interactively)
 
-set -euo pipefail
+set -Eeuo pipefail
 
 ############################################
 # LOGGING
@@ -22,6 +22,48 @@ LOGFILE="$HOME/arch-autoinstall.log"
 } >> "$LOGFILE"
 exec > >(tee -a "$LOGFILE") 2>&1
 
+############################################
+# Error handler — TUI prompt to send log via croc
+############################################
+error_handler() {
+    local exit_code=$? line_num="${1:-?}"
+    echo "" >> "$LOGFILE"
+    echo "ERROR: installer failed at line $line_num (exit code $exit_code)" >> "$LOGFILE"
+
+    if command -v dialog &>/dev/null; then
+        if dialog --clear --title " Installer Error " \
+                  --yesno \
+                  "Installation failed at line $line_num (exit code: $exit_code).\n\nSend the log to another system via croc for analysis?" \
+                  9 62; then
+            clear
+            if ! command -v croc &>/dev/null; then
+                echo "Installing croc..."
+                pacman -Sy --noconfirm croc 2>/dev/null || true
+            fi
+            if command -v croc &>/dev/null; then
+                croc send "$LOGFILE"
+            else
+                echo "croc unavailable — log is at: $LOGFILE"
+            fi
+        else
+            clear
+            echo "Log saved to: $LOGFILE"
+        fi
+    else
+        echo ""
+        echo "Installation failed at line $line_num (exit code $exit_code)."
+        read -rp "Send log via croc? [y/N]: " _croc_ans
+        if [[ "${_croc_ans,,}" == "y" ]]; then
+            command -v croc &>/dev/null || pacman -Sy --noconfirm croc 2>/dev/null || true
+            croc send "$LOGFILE" || true
+        else
+            echo "Log saved to: $LOGFILE"
+        fi
+    fi
+    exit "$exit_code"
+}
+trap 'error_handler $LINENO' ERR
+
 ############################################
 # ANSWERFILE
 ############################################

setup/archbaseos-guided-install.sh

@@ -4,7 +4,7 @@
 # If /answerfile.json exists (e.g. embedded via build.sh --preconf), all prompts
 # are answered from it. Missing fields fall back to interactive prompts.
 
-set -euo pipefail
+set -Eeuo pipefail
 
 ############################################
 # LOGGING
@@ -19,6 +19,48 @@ LOGFILE="$HOME/archbaseos-guided-install.log"
 } >> "$LOGFILE"
 exec > >(tee -a "$LOGFILE") 2>&1
 
+############################################
+# Error handler — TUI prompt to send log via croc
+############################################
+error_handler() {
+    local exit_code=$? line_num="${1:-?}"
+    echo "" >> "$LOGFILE"
+    echo "ERROR: installer failed at line $line_num (exit code $exit_code)" >> "$LOGFILE"
+
+    if command -v dialog &>/dev/null; then
+        if dialog --clear --title " Installer Error " \
+                  --yesno \
+                  "Installation failed at line $line_num (exit code: $exit_code).\n\nSend the log to another system via croc for analysis?" \
+                  9 62; then
+            clear
+            if ! command -v croc &>/dev/null; then
+                echo "Installing croc..."
+                pacman -Sy --noconfirm croc 2>/dev/null || true
+            fi
+            if command -v croc &>/dev/null; then
+                croc send "$LOGFILE"
+            else
+                echo "croc unavailable — log is at: $LOGFILE"
+            fi
+        else
+            clear
+            echo "Log saved to: $LOGFILE"
+        fi
+    else
+        echo ""
+        echo "Installation failed at line $line_num (exit code $exit_code)."
+        read -rp "Send log via croc? [y/N]: " _croc_ans
+        if [[ "${_croc_ans,,}" == "y" ]]; then
+            command -v croc &>/dev/null || pacman -Sy --noconfirm croc 2>/dev/null || true
+            croc send "$LOGFILE" || true
+        else
+            echo "Log saved to: $LOGFILE"
+        fi
+    fi
+    exit "$exit_code"
+}
+trap 'error_handler $LINENO' ERR
+
 ############################################
 # Helper Functions
 ############################################

setup/archiso/overlay/packages.extra

@@ -6,3 +6,5 @@ libfido2
 btop
 fastfetch
 openssh
+dialog
+croc