Add rpa-run-tab skill

A Tebra-style Run tab for desktop PyQt6 bots, built in about 5 minutes:
Trigger button, Excel input card, progress with timer, live log, checkpoint
boxes with time limits, and green/amber/red endings. It is checked with a
fake bot (run_tab.py --selfcheck). The design decisions are in rpa-run-tab/docs/adr.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

rpa-run-tab/templates/rt.py

@@ -0,0 +1,36 @@
+"""Run tab protocol for the bot (ADR-0002). Copy this file next to the bot.
+
+    import rt
+    rt.checkpoint(1)            # checkpoint 1 starts (its time limit starts counting)
+    rt.ui("Signed in", "ok")    # a line the operator sees: kind "", "ok", "warn" or "error"
+    rt.checkpoint_done(1)
+    ...
+    return rt.result(total=40, failed=[("Row 7", "Account not found")])
+
+The bot's entry function returns rt.result(...), and the Run tab prints the summary line.
+A bot that is a plain script (no entry function) calls rt.summary(...) as its last line.
+"""
+import json
+
+SUMMARY = "__RUN_SUMMARY__"
+
+
+def checkpoint(n):
+    print(f"[CPSTATE] active {n}", flush=True)
+
+
+def checkpoint_done(n):
+    print(f"[CPSTATE] done {n}", flush=True)
+
+
+def ui(msg, kind=""):
+    print(f"[UI{':' + kind if kind else ''}] {msg}", flush=True)
+
+
+def result(total, failed=()):
+    failed = [[str(item), str(reason)] for item, reason in failed]
+    return {"total": total, "ok": total - len(failed), "failed": failed}
+
+
+def summary(total, failed=()):
+    print(SUMMARY + json.dumps(result(total, failed)), flush=True)