feat(josh-sync): add rename command for safe target renames

Adds `josh-sync rename <target>` (PE-12): safely rename a sync target's
name, subfolder, and/or subrepo_url in one resumable operation, editing
.josh-sync.yml and migrating its state-branch files atomically instead of
orphaning them. Bumps josh-sync to v2.3.0.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TNXgcFWVgSh3wkQS55cCX6

bin/josh-sync

@@ -11,6 +11,7 @@
 #   onboard <target>  Interactive onboarding (auto-picks reset|adopt strategy)
 #   adopt <target>    Alias for `onboard --mode=adopt`
 #   reset <target>    Reset subrepo to josh-filtered view
+#   rename <target>   Rename a target's name/subfolder/subrepo_url, migrating state
 #   migrate-pr <target> [PR#...] [--all]   Move PRs from archived to new subrepo
 #   status            Show target config and sync state
 #   state show|reset  Manage sync state directly
@@ -46,6 +47,8 @@ source "${JOSH_LIB_DIR}/sync.sh"
 source "${JOSH_LIB_DIR}/adopt.sh"
 # shellcheck source=../lib/onboard.sh
 source "${JOSH_LIB_DIR}/onboard.sh"
+# shellcheck source=../lib/rename.sh
+source "${JOSH_LIB_DIR}/rename.sh"
 
 # ─── Version ────────────────────────────────────────────────────────
 
@@ -82,6 +85,10 @@ Commands:
                     via ls-remote (heads → adopt, empty → reset).
   adopt <target>    Alias for 'onboard --mode=adopt' (kept for back-compat)
   reset <target>    Reset subrepo to josh-filtered view (after merging import PR)
+  rename <target>   Rename a target's name/subfolder/subrepo_url. Edits
+                    .josh-sync.yml and migrates state on the josh-sync-state
+                    branch in one resumable operation. Requires at least one
+                    of --name/--subfolder/--subrepo-url.
   migrate-pr <target> [PR#...] [--all]  Move PRs from archived to new subrepo
   status            Show target config and sync state
   state show <target> [branch]    Show sync state JSON
@@ -103,6 +110,14 @@ Sync flags:
 Onboard flags:
   --mode={reset,adopt}  Override the onboarding strategy
 
+Rename flags:
+  --name NAME           New target name
+  --subfolder PATH      New monorepo subfolder (re-derives josh_filter)
+  --subrepo-url URL     New subrepo git URL
+  --dry-run             Print the planned changes without writing anything
+  --yes                 Skip the confirmation prompt
+  --force               Bypass the concurrency-heuristic warning (only)
+
 Environment:
   JOSH_SYNC_TARGET       Restrict to a single target name
   JOSH_SYNC_STATE_BRANCH State branch name (default: josh-sync-state)
@@ -619,6 +634,46 @@ cmd_reset() {
   done
 }
 
+# ─── Rename Command ─────────────────────────────────────────────────
+
+cmd_rename() {
+  local config_file=".josh-sync.yml"
+  local target_name=""
+  local new_name="" new_subfolder="" new_subrepo_url=""
+  local dry_run=false assume_yes=false force=false
+
+  while [ $# -gt 0 ]; do
+    case "$1" in
+      --config)      config_file="$2"; shift 2 ;;
+      --debug)       export JOSH_SYNC_DEBUG=1; shift ;;
+      --name)        [ $# -ge 2 ] || die "--name requires a value"; new_name="$2"; shift 2 ;;
+      --subfolder)   [ $# -ge 2 ] || die "--subfolder requires a value"; new_subfolder="$2"; shift 2 ;;
+      --subrepo-url) [ $# -ge 2 ] || die "--subrepo-url requires a value"; new_subrepo_url="$2"; shift 2 ;;
+      --dry-run)     dry_run=true; shift ;;
+      --yes)         assume_yes=true; shift ;;
+      --force)       force=true; shift ;;
+      -*) die "Unknown flag: $1" ;;
+      *)  target_name="$1"; shift ;;
+    esac
+  done
+
+  if [ -z "$target_name" ]; then
+    echo "Usage: josh-sync rename <target> [--name NEW] [--subfolder PATH] [--subrepo-url URL] [--dry-run] [--yes] [--force]" >&2
+    parse_config "$config_file"
+    echo "Available targets:" >&2
+    echo "$JOSH_SYNC_TARGETS" | jq -r '.[].name' | sed 's/^/  /' >&2
+    exit 1
+  fi
+
+  if [ -z "$new_name" ] && [ -z "$new_subfolder" ] && [ -z "$new_subrepo_url" ]; then
+    die "At least one of --name, --subfolder, or --subrepo-url is required"
+  fi
+
+  parse_config "$config_file"
+  rename_target "$target_name" "$new_name" "$new_subfolder" "$new_subrepo_url" \
+    "$config_file" "$dry_run" "$assume_yes" "$force"
+}
+
 # ─── Status Command ────────────────────────────────────────────────
 
 cmd_status() {
@@ -934,6 +989,7 @@ main() {
     import)     cmd_import "$@" ;;
     adopt)      cmd_adopt "$@" ;;
     reset)      cmd_reset "$@" ;;
+    rename)     cmd_rename "$@" ;;
     onboard)    cmd_onboard "$@" ;;
     migrate-pr) cmd_migrate_pr "$@" ;;
     status)     cmd_status "$@" ;;