docs: add initial agent documentation (#260)

* docs: add initial agent documentation

* docs: format AGENTS.md for improved readability

Author: pratapalakshmi

AGENTS.md

@@ -0,0 +1,47 @@
+# Developer Docs Agent Context
+
+## Purpose
+
+Internal developer documentation for Plane EE.
+
+## Structure
+
+```text
+docs/
+  api-reference/        # REST API docs — 30+ resource categories (issues, cycles, modules, pages, etc.)
+  dev-tools/            # Developer tooling guides
+    agents/             # Agent development (overview, building, signals, best practices)
+    build-plane-app/    # App development guide
+    mcp-server.md       # MCP server setup
+    mcp-server-claude-code.md  # MCP server with Claude Code
+    plane-compose.md    # Plane Compose reference
+    openapi-specification.md
+    intro-webhooks.md
+  self-hosting/         # Deployment and configuration guides
+    methods/            # Docker, Kubernetes, Podman, Coolify, Portainer, one-click, airgapped
+      install-methods-commercial/  # Commercial Docker Compose and Kubernetes
+    govern/             # Auth, integrations, settings, SSL, DNS, env vars
+      integrations/     # GitHub, GitLab, Slack, Sentry
+    manage/             # Backup/restore, Prime CLI, update Plane, logs, user management
+    troubleshoot/       # CLI errors, installation, license, storage errors
+```
+
+## Key Documentation Paths
+
+- `self-hosting/methods/kubernetes.md` - K8s deployment guide
+- `self-hosting/methods/install-methods-commercial/` - Commercial Docker Compose and Kubernetes
+- `self-hosting/govern/integrations/` - GitHub, GitLab, Slack, Sentry
+- `self-hosting/govern/plane-ai.md` - AI features configuration
+- `self-hosting/govern/environment-variables.md` - All env var reference
+- `self-hosting/govern/authentication.md` - Auth setup (LDAP, OIDC, SAML, OAuth)
+- `self-hosting/govern/reverse-proxy.md` - Reverse proxy setup
+- `self-hosting/manage/` - Instance management, backup/restore, Prime CLI
+- `dev-tools/agents/` - Agent development docs
+- `dev-tools/mcp-server.md` and `mcp-server-claude-code.md` - MCP server docs
+
+## Important Notes
+
+- Not all features are documented immediately after release
+- Check both public docs (docs.plane.so) and internal docs
+- `self-hosting/govern/plane-ai.md` is the correct path for AI config (not `self-hosting/plane-ai.md`)
+- API reference covers 30+ resource categories — check `docs/api-reference/` for the full list