feat: add DBOS skills for TypeScript, Python, and Go (#94)

Add three DBOS SDK skills with reference documentation for building
reliable, fault-tolerant applications with durable workflows.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

skills/dbos-python/references/pattern-sleep.md

@@ -0,0 +1,58 @@
+---
+title: Use Durable Sleep for Delayed Execution
+impact: MEDIUM
+impactDescription: Survives restarts and can span days or weeks
+tags: sleep, delay, schedule, durable
+---
+
+## Use Durable Sleep for Delayed Execution
+
+Use `DBOS.sleep()` for durable delays that survive restarts. The wakeup time is persisted in the database.
+
+**Incorrect (regular sleep):**
+
+```python
+import time
+
+@DBOS.workflow()
+def delayed_task(delay_seconds, task):
+    # Regular sleep is lost on restart!
+    time.sleep(delay_seconds)
+    run_task(task)
+```
+
+**Correct (durable sleep):**
+
+```python
+@DBOS.workflow()
+def delayed_task(delay_seconds, task):
+    # Durable sleep - survives restarts
+    DBOS.sleep(delay_seconds)
+    run_task(task)
+```
+
+Use cases for durable sleep:
+- Schedule a task for the future
+- Wait between retries
+- Implement delays spanning hours, days, or weeks
+
+Example: Schedule a reminder:
+
+```python
+@DBOS.workflow()
+def send_reminder(user_id: str, message: str, delay_days: int):
+    # Sleep for days - survives any restart
+    DBOS.sleep(delay_days * 24 * 60 * 60)
+    send_notification(user_id, message)
+```
+
+For async workflows, use `DBOS.sleep_async()`:
+
+```python
+@DBOS.workflow()
+async def async_delayed_task():
+    await DBOS.sleep_async(60)
+    await run_async_task()
+```
+
+Reference: [Durable Sleep](https://docs.dbos.dev/python/tutorials/workflow-tutorial#durable-sleep)