chore(git-workflow): add 3-repo feature branch skills + helper scripts

scripts/git-workflow/repo-status.sh

@@ -0,0 +1,63 @@
+#!/bin/bash
+# Emit one JSON line per repo describing its state.
+# Fields: repo, path, branch, dirty, ahead, behind, head_sha, main, rebase_in_progress, up_to_date_with_main
+# "up_to_date_with_main" means origin/<main> is an ancestor of HEAD (i.e. rebase not needed).
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# shellcheck source=./repos.sh
+source "$SCRIPT_DIR/repos.sh"
+
+json_escape() {
+    # Minimal JSON string escape: backslash and double-quote only. Branch/sha never contain control chars in practice.
+    local s="$1"
+    s="${s//\\/\\\\}"
+    s="${s//\"/\\\"}"
+    printf '%s' "$s"
+}
+
+for repo in "${REPOS[@]}"; do
+    p=$(repo_path "$repo")
+    main=$(repo_main "$repo")
+
+    branch=$(git -C "$p" branch --show-current || echo "")
+    head_sha=$(git -C "$p" rev-parse --short HEAD)
+
+    if [ -z "$(git -C "$p" status --porcelain)" ]; then
+        dirty="false"
+    else
+        dirty="true"
+    fi
+
+    ahead=0
+    behind=0
+    if [ -n "$branch" ] && git -C "$p" rev-parse --verify --quiet "origin/$main" >/dev/null; then
+        read -r behind ahead < <(git -C "$p" rev-list --left-right --count "origin/$main...HEAD" 2>/dev/null || echo "0 0")
+    fi
+
+    if [ -d "$p/.git/rebase-merge" ] || [ -d "$p/.git/rebase-apply" ]; then
+        rebase="true"
+    else
+        rebase="false"
+    fi
+
+    up_to_date="false"
+    if git -C "$p" rev-parse --verify --quiet "origin/$main" >/dev/null; then
+        if git -C "$p" merge-base --is-ancestor "origin/$main" HEAD 2>/dev/null; then
+            up_to_date="true"
+        fi
+    fi
+
+    printf '{"repo":"%s","path":"%s","branch":"%s","dirty":%s,"ahead":%s,"behind":%s,"head_sha":"%s","main":"%s","rebase_in_progress":%s,"up_to_date_with_main":%s}\n' \
+        "$(json_escape "$repo")" \
+        "$(json_escape "$p")" \
+        "$(json_escape "$branch")" \
+        "$dirty" \
+        "$ahead" \
+        "$behind" \
+        "$(json_escape "$head_sha")" \
+        "$(json_escape "$main")" \
+        "$rebase" \
+        "$up_to_date"
+done