feat: add pipeline engine with approval flow and file triggers

Sequential step executor (script, claude_prompt, approval, api_call,
template, skyvern placeholder), reaction-based approvals, file upload
trigger matching, portal API state sync.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pipelines/state.py

@@ -0,0 +1,62 @@
+"""Pipeline state management — syncs with matrixhost portal API."""
+
+import logging
+from datetime import datetime, timezone
+
+import httpx
+
+logger = logging.getLogger(__name__)
+
+
+class PipelineStateManager:
+    """Manages pipeline state via portal API."""
+
+    def __init__(self, portal_url: str, api_key: str):
+        self.portal_url = portal_url.rstrip("/")
+        self.api_key = api_key
+
+    async def fetch_active_pipelines(self) -> list[dict]:
+        async with httpx.AsyncClient(timeout=15.0) as client:
+            resp = await client.get(
+                f"{self.portal_url}/api/pipelines/active",
+                headers={"x-api-key": self.api_key},
+            )
+            resp.raise_for_status()
+            data = resp.json()
+        return data.get("pipelines", [])
+
+    async def create_execution(self, pipeline_id: str, trigger_data: dict | None = None) -> dict:
+        async with httpx.AsyncClient(timeout=10.0) as client:
+            resp = await client.post(
+                f"{self.portal_url}/api/pipelines/{pipeline_id}/execution",
+                headers={"x-api-key": self.api_key},
+                json={"triggerData": trigger_data},
+            )
+            resp.raise_for_status()
+            data = resp.json()
+        return data["execution"]
+
+    async def update_execution(self, execution_id: str, **kwargs) -> None:
+        try:
+            async with httpx.AsyncClient(timeout=10.0) as client:
+                await client.put(
+                    f"{self.portal_url}/api/pipelines/executions/{execution_id}",
+                    headers={"x-api-key": self.api_key},
+                    json=kwargs,
+                )
+        except Exception:
+            logger.warning("Failed to update execution %s", execution_id, exc_info=True)
+
+    async def fetch_pending_approvals(self) -> list[dict]:
+        try:
+            async with httpx.AsyncClient(timeout=10.0) as client:
+                resp = await client.get(
+                    f"{self.portal_url}/api/pipelines/executions/pending",
+                    headers={"x-api-key": self.api_key},
+                )
+                resp.raise_for_status()
+                data = resp.json()
+            return data.get("executions", [])
+        except Exception:
+            logger.debug("Failed to fetch pending approvals", exc_info=True)
+            return []