publisher: themed calendar, NIP-01 nostr adapter, gated brand images

- calendar: one draft per theme/channel (idempotent), rotated schedule
- human gate: approve() audited; AUTONOMOUS_MODE has no effect here by design
- nostr (primary): in-repo NIP-01 client (D4) — canonical serialization,
  sha256 id, BIP-340 schnorr sign via coincurve with zero aux randomness
  (deterministic), pure-python reference verification before publish,
  per-relay publish with isolated errors, event id stored as post_ref
- facebook/instagram adapters: exist but refuse to run unless explicitly
  enabled via env (default deployment never touches Meta)
- images: Pillow brand templates (bh gold / hc orange), 1080x1350,
  template-driven typeset design (not AI-generated media)
- failure isolation: config errors audited, item stays approved

tests: 12 new (event roundtrip+tamper, determinism, key validation,
calendar idempotence, approve gate, nostr happy path, future schedule,
clean config failure, disabled meta adapters, image render) — 41 total

cayceops/components/publisher/adapters.py

@@ -0,0 +1,61 @@
+"""Optional Facebook/Instagram adapters (Graph API).
+
+DISABLED BY DEFAULT. Each adapter refuses to run unless its enable flag is
+true (``CAYCE_OPS_ENABLE_FACEBOOK`` / ``CAYCE_OPS_ENABLE_INSTAGRAM``), so the
+default deployment never touches Meta endpoints. Tokens are env-only and are
+never logged.
+"""
+
+from __future__ import annotations
+
+import json
+import urllib.parse
+import urllib.request
+
+GRAPH = "https://graph.facebook.com/v21.0"
+
+
+def _post(url: str, payload: dict) -> dict:
+    data = urllib.parse.urlencode(payload).encode()
+    req = urllib.request.Request(url, data=data, method="POST")  # noqa: S310
+    with urllib.request.urlopen(req, timeout=30) as resp:
+        return json.loads(resp.read().decode())
+
+
+def post_facebook(cfg, caption: str, media_path: str | None = None) -> dict:
+    """Post to the page feed (text) or /photos (with local media). Gated."""
+    if not cfg.enable_facebook:
+        raise PermissionError("facebook adapter disabled (CAYCE_OPS_ENABLE_FACEBOOK=false)")
+    if not cfg.facebook_page_token:
+        raise ValueError("CAYCE_OPS_FACEBOOK_PAGE_TOKEN missing")
+    if media_path:
+        # photo posts require a reachable URL or multipart upload; we use the
+        # simple URL form — media must be hosted (out of scope for local files)
+        result = _post(
+            f"{GRAPH}/me/photos",
+            {"url": media_path, "caption": caption, "access_token": cfg.facebook_page_token},
+        )
+    else:
+        result = _post(
+            f"{GRAPH}/me/feed",
+            {"message": caption, "access_token": cfg.facebook_page_token},
+        )
+    return {"post_id": result.get("post_id") or result.get("id", "")}
+
+
+def post_instagram(cfg, caption: str, image_url: str) -> dict:
+    """Two-step IG publish (container -> publish). Gated."""
+    if not cfg.enable_instagram:
+        raise PermissionError("instagram adapter disabled (CAYCE_OPS_ENABLE_INSTAGRAM=false)")
+    if not cfg.instagram_user_id:
+        raise ValueError("CAYCE_OPS_INSTAGRAM_USER_ID missing")
+    token = cfg.facebook_page_token  # IG Graph publishing uses the page token
+    container = _post(
+        f"{GRAPH}/{cfg.instagram_user_id}/media",
+        {"image_url": image_url, "caption": caption, "access_token": token},
+    )
+    published = _post(
+        f"{GRAPH}/{cfg.instagram_user_id}/media_publish",
+        {"creation_id": container["id"], "access_token": token},
+    )
+    return {"post_id": published.get("id", "")}