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/workflow-determinism.md

@@ -0,0 +1,53 @@
+---
+title: Keep Workflows Deterministic
+impact: CRITICAL
+impactDescription: Non-deterministic workflows cannot recover correctly
+tags: workflow, determinism, recovery, reliability
+---
+
+## Keep Workflows Deterministic
+
+Workflow functions must be deterministic: given the same inputs and step return values, they must invoke the same steps in the same order. Non-deterministic operations must be moved to steps.
+
+**Incorrect (non-deterministic workflow):**
+
+```python
+import random
+
+@DBOS.workflow()
+def example_workflow():
+    # Random number in workflow breaks recovery!
+    choice = random.randint(0, 1)
+    if choice == 0:
+        step_one()
+    else:
+        step_two()
+```
+
+**Correct (non-determinism in step):**
+
+```python
+import random
+
+@DBOS.step()
+def generate_choice():
+    return random.randint(0, 1)
+
+@DBOS.workflow()
+def example_workflow():
+    # Random number generated in step - result is saved
+    choice = generate_choice()
+    if choice == 0:
+        step_one()
+    else:
+        step_two()
+```
+
+Non-deterministic operations that must be in steps:
+- Random number generation
+- Getting current time
+- Accessing external APIs
+- Reading files
+- Database queries (use transactions or steps)
+
+Reference: [Workflow Determinism](https://docs.dbos.dev/python/tutorials/workflow-tutorial#determinism)