Initial scaffold: API service, K8s operator, and CRDs

Forgebot is a K8s operator + API service for dispatching AI agent
jobs from git forge commands. Includes:

- CRDs: AgentPool, AgentTask, ProviderQueue, RepositoryBinding
- API server with webhook handler, task queue, and comment proxy
- Operator controllers for task scheduling and job management
- Gitea provider with webhook parsing and signature verification
- PostgreSQL database with auto-migration
- Woodpecker CI pipelines and multi-stage Dockerfiles

config/samples/repositorybinding.yaml

@@ -0,0 +1,29 @@
+---
+apiVersion: forgebot.unkin.net/v1alpha1
+kind: RepositoryBinding
+metadata:
+  name: artifactapi
+  namespace: forgebot
+spec:
+  repository: unkin/artifactapi
+  providerQueueRef: gitea-queue
+  agentPoolRef: default-pool
+  allowedUsers:
+    - unkinben
+  allowedCommands:
+    - plan
+    - review
+    - implement
+    - test
+    - fix
+  skillMapping:
+    - command: plan
+      skill: plan
+    - command: review
+      skill: review
+    - command: implement
+      skill: implement
+    - command: test
+      skill: test
+    - command: fix
+      skill: fix