Add animekai source with 1anime direct-MP4 backend (independent CDN)

animekai.be fronted two server backends per episode: megaplay.buzz
(same player/CDN family as hianime — 403s our egress IP) and
my.1anime.site (direct progressive MP4, independent CDN — verified
serving our IP at ~2.4MB/s). This is the rescue path around the
MegaPlay Cloudflare block, per the ani-cli #1945/#1918 work.

- providers/animekai.py: standard interface, per-episode backend
  dispatch (1anime first, then megaplay), same listed-but-dead ->
  raise semantics as hianime. All endpoints ride the shared TTL cache
  (no re-fetching on repeat UI hits).
- upstream.py: megaplay_master() moved out of hianime — the MegaPlay
  chain (embed -> data-id -> getSourcesNew -> enc decrypt -> CDN proof)
  is now shared by every provider fronting that player.
- app.py: /stream forwards Range for progressive files (206 +
  Content-Range passthrough, partial bodies never LRU-cached, 8MB cap
  on the parallel path so a 250MB MP4 can't pin RAM). api_stream
  reports hls=true/false from the URL — the player kind is a property
  of the URL, so future stream types slot in without app changes.
- app.js: hls===false -> native <video> (existing Range-seeking),
  hls.js path untouched.
- run.sh: ANI_SOURCE=animekai,hianime,anidb,anikoto (revert to the old
  chain when the MegaPlay block lifts).
- tests: test_animekai.py (offline: interface, enc decrypt, /stream
  Range via monkeypatched network) + test_animekai_live.py (opt-in
  ANI_LIVE=1 end-to-end, skipped by default so the suite never touches
  animekai.be).

tests/test_animekai_live.py

@@ -0,0 +1,103 @@
+"""test_animekai_live.py — LIVE smoke tests for the animekai provider.
+
+Skipped by default so the suite never touches animekai.be (politeness:
+the provider must not be spammed by CI or local test runs). Enable with:
+
+    ANI_LIVE=1 .venv/bin/pytest tests/test_animekai_live.py -q -s
+
+Every call rides the provider's _cached TTL cache, so one run is a
+handful of requests, not a crawl.
+"""
+import base64
+import os
+import sys
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(ROOT))
+
+live = pytest.mark.skipif(
+    os.environ.get("ANI_LIVE") != "1",
+    reason="live upstream test: run with ANI_LIVE=1")
+
+
+@live
+def test_search_shape():
+    from server.providers import animekai as a
+    r = a.search("one piece")
+    assert r and all(set(x) >= {"id", "slug_id", "name"} for x in r), r[:2]
+    print("\nsearch:", [(x["name"], x["slug_id"]) for x in r[:3]])
+
+
+@live
+def test_details_episodes_languages():
+    from server.providers import animekai as a
+    r = a.search("one piece")
+    top = next(x for x in r if x["name"].lower().startswith("one piece"))
+    d = a.details(top["slug_id"])
+    print("\ndetails:", {k: (str(v)[:60] if v else v) for k, v in d.items()
+                        if k != "seasons"})
+    assert d["name"] and d["id"], d
+    eps = a.episodes(d["id"])
+    assert eps and eps[0]["number"] == 1, eps[:2]
+    print("episodes:", len(eps), "first:", eps[0])
+    langs = a.languages(eps[0]["id"])
+    print("langs ep1:", langs)
+    assert langs, "ep1 should have at least sub"
+
+
+@live
+def test_master_resolves_and_stream_proxy_serves_range(monkeypatch):
+    """Full path: provider resolves a stream, and the in-process /stream
+    proxy serves it with Range (206 + chunk). server.app import is safe
+    here: the CDN probe is idle-gated (no upstream fetch until a play)."""
+    # stream_meta's allowlist walks the ANI_SOURCE chain; point it at
+    # animekai (as run.sh does) so the resolved host is permitted
+    monkeypatch.setenv("ANI_SOURCE", "animekai")
+    from server.providers import animekai as a
+    # Sparks of Tomorrow's early eps were observed on 1anime servers
+    # (independent CDN); the browse sort is most_viewed, so pick the title
+    # by name, not position, then scan its first episodes for a resolver.
+    r = a.search("sparks of tomorrow")
+    top = next((x for x in r if "sparks" in x["name"].lower()), r[0])
+    d = a.details(top["slug_id"])
+    eps = a.episodes(d["id"])
+    got = None
+    for e in eps[:5]:
+        for lang in ("jpn", "eng"):
+            try:
+                got = a.master_m3u8(e["id"], lang)
+            except Exception as ex:
+                print(f"\nep{e['number']} {lang}: {ex}")
+            if got:
+                break
+        if got:
+            break
+    assert got, "no server resolved for ep1-3 (both backends dead?)"
+    print("\nresolved:", got)
+
+    # host must be allowlisted (that IS the /stream permit)
+    from urllib.parse import urlparse
+    meta = a.stream_meta(got)
+    assert meta is not None, f"provider did not register host for {got}"
+
+    # in-process /stream Range check (direct handler call, no server spawn)
+    import asyncio
+    import types
+    import server.app as app_mod
+    token = base64.urlsafe_b64encode(got.encode()).decode()
+    rng = None if got.endswith(".m3u8") else "bytes=0-1023"
+    req = types.SimpleNamespace(headers={"range": rng} if rng else {})
+    resp = app_mod.stream(token, request=req)
+
+    async def _drain(it):
+        return b"".join([c async for c in it])
+    body = (asyncio.run(_drain(resp.body_iterator)) if getattr(resp, "body_iterator", None) is not None
+            else resp.body)
+    if got.endswith(".m3u8"):
+        assert resp.status_code == 200 and b"#EXTM3U" in body
+    else:
+        assert resp.status_code == 206 and len(body) == 1024, resp.status_code
+    print("proxy:", resp.status_code, len(body), "b")