URGENT FIX: uninstall preserves user data by default (was destructive)

User reported losing 6 months of accumulated work — projects, plans,
custom commands/skills, file-history, history.jsonl — because
uclaude_uninstall.sh did `rm -rf ~/.claude` without warning or backup.

Same destruction risk in codex/gemini/qwen uninstallers (each has its
own ~/.tool-name/ dir with user data).

Fix:
- claude/uclaude_uninstall.sh: DEFAULT preserves projects/, history.jsonl,
  commands/, plans/, file-history/, plugins/. Only removes settings.json
  + cache/ (which Claude regenerates). settings.json backed up first.
- Explicit opt-in to wipe everything: UCLAUDE_PURGE_USER_DATA=1
  (and even then creates a tar backup before delete)
- README guidance updated

NEVER again should an uninstaller silently destroy user data.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

claude/uclaude_uninstall.sh

@@ -42,21 +42,68 @@ else
 fi
 
 # ---- Remove settings ----
+# DEFAULT: PRESERVE user data (projects, history, plans, commands, plugins,
+# file-history). Only delete settings.json + cache/. User data took months
+# to accumulate — never destroy without explicit opt-in.
+#
+# Set UCLAUDE_PURGE_USER_DATA=1 to wipe the entire ~/.claude/ directory
+# (the old destructive behavior).
+
+PURGE_USER_DATA="${UCLAUDE_PURGE_USER_DATA:-0}"
+TIMESTAMP=$(date +%Y%m%d%H%M%S)
 
 for user_home in /root /home/*; do
     CLAUDE_DIR="$user_home/.claude"
     if [ -d "$CLAUDE_DIR" ]; then
-        info "Removing $CLAUDE_DIR..."
-        rm -rf "$CLAUDE_DIR"
-        log "Removed $CLAUDE_DIR"
+        if [ "$PURGE_USER_DATA" = "1" ]; then
+            # Explicit opt-in: tar backup first, then wipe
+            BACKUP_TAR="$user_home/.claude.uninstall-backup.${TIMESTAMP}.tar.gz"
+            info "PURGE mode — backing up to $BACKUP_TAR before delete..."
+            tar -czf "$BACKUP_TAR" -C "$user_home" .claude 2>/dev/null && \
+                log "Backup saved: $BACKUP_TAR" || \
+                warn "Backup failed — aborting purge to preserve data"
+            if [ -f "$BACKUP_TAR" ]; then
+                rm -rf "$CLAUDE_DIR"
+                log "Removed $CLAUDE_DIR (restore: tar -xzf $BACKUP_TAR -C $user_home)"
+            fi
+        else
+            # Default: preserve user data, only remove patcher-managed files
+            info "Cleaning $CLAUDE_DIR (preserving user data)..."
+            for f in settings.json settings.local.json .patcher.config.cache.json; do
+                if [ -f "$CLAUDE_DIR/$f" ]; then
+                    # Backup settings.json before delete (env vars are
+                    # easy to recreate, but user may have customized)
+                    cp "$CLAUDE_DIR/$f" "$CLAUDE_DIR/${f}.uninstall.bak.${TIMESTAMP}"
+                    rm -f "$CLAUDE_DIR/$f"
+                    log "Removed $CLAUDE_DIR/$f (backup: ${f}.uninstall.bak.${TIMESTAMP})"
+                fi
+            done
+            # Optionally clean cache/ (safe — Claude regenerates on next run)
+            if [ -d "$CLAUDE_DIR/cache" ]; then
+                rm -rf "$CLAUDE_DIR/cache"
+                log "Removed $CLAUDE_DIR/cache (will regenerate)"
+            fi
+            log "PRESERVED in $CLAUDE_DIR: projects/, history.jsonl, commands/, plans/, file-history/, plugins/, etc."
+        fi
     fi
     CLAUDE_JSON="$user_home/.claude.json"
     if [ -f "$CLAUDE_JSON" ]; then
+        # Backup before delete (.claude.json holds onboarding + recent
+        # session refs — useful to keep for restore).
+        cp "$CLAUDE_JSON" "${CLAUDE_JSON}.uninstall.bak.${TIMESTAMP}"
         rm -f "$CLAUDE_JSON"
-        log "Removed $CLAUDE_JSON"
+        log "Removed $CLAUDE_JSON (backup: ${CLAUDE_JSON}.uninstall.bak.${TIMESTAMP})"
     fi
 done
 
+if [ "$PURGE_USER_DATA" != "1" ]; then
+    echo
+    info "User data PRESERVED. To wipe everything:"
+    info "  UCLAUDE_PURGE_USER_DATA=1 sudo bash uclaude_uninstall.sh"
+    info "(That mode creates a tar backup first, even on purge)"
+    echo
+fi
+
 # ---- Remove env vars from shell rc files ----
 
 for user_home in /root /home/*; do