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-golang/references/queue-concurrency.md

@@ -0,0 +1,49 @@
+---
+title: Control Queue Concurrency
+impact: HIGH
+impactDescription: Prevents resource exhaustion with concurrent limits
+tags: queue, concurrency, workerConcurrency, limits
+---
+
+## Control Queue Concurrency
+
+Queues support worker-level and global concurrency limits to prevent resource exhaustion.
+
+**Incorrect (no concurrency control):**
+
+```go
+queue := dbos.NewWorkflowQueue(ctx, "heavy_tasks") // No limits - could exhaust memory
+```
+
+**Correct (worker concurrency):**
+
+```go
+// Each process runs at most 5 tasks from this queue
+queue := dbos.NewWorkflowQueue(ctx, "heavy_tasks",
+	dbos.WithWorkerConcurrency(5),
+)
+```
+
+**Correct (global concurrency):**
+
+```go
+// At most 10 tasks run across ALL processes
+queue := dbos.NewWorkflowQueue(ctx, "limited_tasks",
+	dbos.WithGlobalConcurrency(10),
+)
+```
+
+**In-order processing (sequential):**
+
+```go
+// Only one task at a time - guarantees order
+serialQueue := dbos.NewWorkflowQueue(ctx, "sequential_queue",
+	dbos.WithGlobalConcurrency(1),
+)
+```
+
+Worker concurrency is recommended for most use cases. Take care with global concurrency as any `PENDING` workflow on the queue counts toward the limit, including workflows from previous application versions.
+
+When using worker concurrency, each process must have a unique `ExecutorID` set in configuration (this is automatic with DBOS Conductor or Cloud).
+
+Reference: [Managing Concurrency](https://docs.dbos.dev/golang/tutorials/queue-tutorial#managing-concurrency)