fix(subscribestar): inject the 18+ age cookie on every SubscribeStar domain

The cookie was pinned to .subscribestar.adult only; cookies are
domain-scoped, so sources on subscribestar.art (Elasid, event #54116)
never sent it and every poll 302d to /age_confirmation_warning. Emit
one line per domain (.com/.adult/.art) with a per-domain presence
check, and admit .art in the platform url_pattern.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CDgx8bQS5YrGRK76v8HUnM

backend/app/services/platforms/subscribestar.py

@@ -14,9 +14,11 @@
    `_personalization_id` age-confirmation cookie that the user can't
    easily refresh — SubscribeStar's frontend JS uses localStorage to
    suppress the age popup once dismissed. gallery-dl's own login flow
-   sidesteps this by setting `18_plus_agreement_generic=true` on
-   `.subscribestar.adult`; we mirror that for cookies captured via the
-   extension.
+   sidesteps this by setting `18_plus_agreement_generic=true`; we mirror
+   that for cookies captured via the extension — on EVERY SubscribeStar
+   domain, because cookies are domain-scoped and the wall exists on all
+   of them: an .adult-only line never rides along to a .art creator page
+   (Elasid, event #54116 — every poll 302'd to /age_confirmation_warning).
 """
 
 from .base import GD_DEFAULTS, PlatformInfo, str_id_value
@@ -29,20 +31,31 @@ def derive_post_url(data: dict) -> str | None:
     return None
 
 
+# All domains SubscribeStar serves creators from; the age wall gates each.
+_SS_DOMAINS = (".subscribestar.com", ".subscribestar.adult", ".subscribestar.art")
+
+
 def augment_cookies(netscape: str) -> str:
-    if "18_plus_agreement_generic" in netscape:
-        return netscape
     # Far-future expiry — gallery-dl's own login flow sets this with no
     # explicit expiry; the server only checks presence/value.
     expiry = 4102444800  # 2100-01-01 UTC
-    line = "\t".join([
-        ".subscribestar.adult", "TRUE", "/", "TRUE",
-        str(expiry), "18_plus_agreement_generic", "true",
-    ])
     body = netscape.rstrip("\n")
     if not body:
         body = "# Netscape HTTP Cookie File"
-    return body + "\n" + line + "\n"
+    lines = netscape.splitlines()
+    for domain in _SS_DOMAINS:
+        # Per-domain presence check: captured cookies carrying the age
+        # cookie for one domain must not suppress injection on the others.
+        if any(
+            line.startswith(domain + "\t") and "18_plus_agreement_generic" in line
+            for line in lines
+        ):
+            continue
+        body += "\n" + "\t".join([
+            domain, "TRUE", "/", "TRUE",
+            str(expiry), "18_plus_agreement_generic", "true",
+        ])
+    return body + "\n"
 
 
 INFO = PlatformInfo(
@@ -51,10 +64,11 @@ INFO = PlatformInfo(
     description="Download posts from SubscribeStar creators",
     auth_type="cookies",
     requires_auth=True,
-    url_pattern=r"^https?://(www\.)?subscribestar\.(com|adult)/",
+    url_pattern=r"^https?://(www\.)?subscribestar\.(com|adult|art)/",
     url_examples=[
         "https://subscribestar.adult/example_artist",
         "https://www.subscribestar.com/example_artist",
+        "https://subscribestar.art/example_artist",
     ],
     default_config={**GD_DEFAULTS, "content_types": ["all"]},
     derive_post_url=derive_post_url,