Initial commit: agentic chat app for IBM Storage Scale REST API v3

Adds a Python package that wraps the Storage Scale /scalemgmt/v3 management
API behind a Claude-driven tool-use loop. Ships a Rich-styled terminal REPL
and a Streamlit web UI sharing the same Agent/Dispatcher/GPFSClient stack.

Guardrails are env-driven (.env): read-only by default; writes and DELETE
gated by GPFS_ALLOW_WRITES / GPFS_ALLOW_DESTRUCTIVE; optional path
allow/deny regex; mutating calls require operator confirmation. Free-text
GPFS_INSTRUCTIONS (or GPFS_INSTRUCTIONS_FILE) appended to the system prompt.

The system prompt also includes a curated v3 endpoint reference compiled
from IBM Storage Scale 5.2.3 / 6.0.0 documentation so the agent doesn't
have to guess endpoint shapes for common operations.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

gpfs_agent/gpfs_client.py

@@ -0,0 +1,74 @@
+from __future__ import annotations
+
+import json
+from typing import Any, Optional
+
+import httpx
+
+from .config import Config
+
+
+class GPFSError(RuntimeError):
+    def __init__(self, status: int, body: Any, method: str, url: str) -> None:
+        super().__init__(f"{method} {url} -> HTTP {status}")
+        self.status = status
+        self.body = body
+        self.method = method
+        self.url = url
+
+
+class GPFSClient:
+    def __init__(self, cfg: Config) -> None:
+        self._cfg = cfg
+        self._client = httpx.Client(
+            base_url=cfg.gpfs_base,
+            auth=(cfg.gpfs_username, cfg.gpfs_password),
+            verify=cfg.verify_tls,
+            timeout=cfg.timeout,
+            headers={
+                "Accept": "application/json",
+                "Content-Type": "application/json",
+            },
+        )
+
+    def close(self) -> None:
+        self._client.close()
+
+    def __enter__(self) -> "GPFSClient":
+        return self
+
+    def __exit__(self, *_: object) -> None:
+        self.close()
+
+    def request(
+        self,
+        method: str,
+        path: str,
+        params: Optional[dict[str, Any]] = None,
+        body: Optional[dict[str, Any]] = None,
+    ) -> dict[str, Any]:
+        if not path.startswith("/"):
+            path = "/" + path
+
+        response = self._client.request(
+            method=method.upper(),
+            url=path,
+            params=params or None,
+            content=json.dumps(body) if body is not None else None,
+        )
+
+        text = response.text
+        data: Any
+        try:
+            data = response.json() if text else None
+        except json.JSONDecodeError:
+            data = None
+
+        return {
+            "status": response.status_code,
+            "ok": response.is_success,
+            "url": str(response.request.url),
+            "method": method.upper(),
+            "data": data,
+            "text": None if data is not None else text,
+        }