Add anipy-cli download fallback

Add an optional config toggle that retries failed ani-cli downloads with anipy-cli, expose fallback runtime status in the config page, and update release docs and tests for the new behavior.

app_support.py

@@ -23,6 +23,7 @@ from uuid import uuid4
 
 PROJECT_ROOT = Path(__file__).resolve().parent
 ANI_CLI = os.environ.get("ANI_CLI_BIN") or shutil.which("ani-cli") or "ani-cli"
+ANIPY_CLI = os.environ.get("ANIPY_CLI_BIN") or shutil.which("anipy-cli") or "anipy-cli"
 APP_NAME = "ani-cli-web"
 VERSION_FILE = PROJECT_ROOT / "VERSION"
 CHANGELOG_FILE = PROJECT_ROOT / "CHANGELOG.md"
@@ -290,6 +291,7 @@ DEFAULT_CONFIG = {
     "download_dir": default_download_dir(),
     "mode": os.environ.get("ANI_CLI_MODE", "sub"),
     "quality": os.environ.get("ANI_CLI_QUALITY", "best"),
+    "anipy_cli_fallback_enabled": False,
     "watchlist_auto_refresh_enabled": False,
     "watchlist_auto_refresh_minutes": WATCHLIST_AUTO_REFRESH_DEFAULT_MINUTES,
     "watchlist_refresh_delay_seconds": WATCHLIST_REFRESH_DELAY_DEFAULT_SECONDS,
@@ -445,6 +447,7 @@ def normalize_config(data):
     if quality.endswith("p") and quality[:-1].isdigit():
         quality = quality[:-1]
     download_dir = str(config.get("download_dir") or DEFAULT_CONFIG["download_dir"])
+    anipy_cli_fallback_enabled = config.get("anipy_cli_fallback_enabled")
     auto_refresh_enabled = config.get("watchlist_auto_refresh_enabled")
     auto_refresh_minutes = config.get("watchlist_auto_refresh_minutes")
     refresh_delay_seconds = config.get("watchlist_refresh_delay_seconds")
@@ -461,6 +464,10 @@ def normalize_config(data):
     auth_username = str(config.get("auth_username") or "").strip()
     auth_password = str(config.get("auth_password") or "").strip()
 
+    if isinstance(anipy_cli_fallback_enabled, str):
+        anipy_cli_fallback_enabled = anipy_cli_fallback_enabled.strip().lower() in {"1", "true", "yes", "on"}
+    else:
+        anipy_cli_fallback_enabled = bool(anipy_cli_fallback_enabled)
     if isinstance(auto_refresh_enabled, str):
         auto_refresh_enabled = auto_refresh_enabled.strip().lower() in {"1", "true", "yes", "on"}
     else:
@@ -494,6 +501,7 @@ def normalize_config(data):
     config["mode"] = mode if mode in MODE_CHOICES else "sub"
     config["quality"] = quality if quality in QUALITY_CHOICES else "best"
     config["download_dir"] = str(Path(download_dir).expanduser())
+    config["anipy_cli_fallback_enabled"] = anipy_cli_fallback_enabled
     config["watchlist_auto_refresh_enabled"] = auto_refresh_enabled
     config["watchlist_auto_refresh_minutes"] = auto_refresh_minutes
     config["watchlist_refresh_delay_seconds"] = refresh_delay_seconds
@@ -961,6 +969,13 @@ def strip_control(value):
     return re.sub(r"\x1b\[[0-9;?]*[A-Za-z]", "", str(value)).replace("\r", "\n")
 
 
+def cli_executable_exists(command):
+    text = str(command or "").strip()
+    if not text:
+        return False
+    return bool(shutil.which(text) or (Path(text).exists() and os.access(text, os.X_OK)))
+
+
 def printable_command(command):
     return " ".join(sh_quote(part) for part in command)
 
@@ -1081,8 +1096,8 @@ def finalize_library_files(job):
     episode_offset = normalize_episode_offset(job.get("episode_offset"))
     target_dir.mkdir(parents=True, exist_ok=True)
     files = sorted(
-        [path for path in staging_dir.iterdir() if path.is_file()],
-        key=lambda path: (path.stat().st_mtime, path.name),
+        [path for path in staging_dir.rglob("*") if path.is_file()],
+        key=lambda path: (path.stat().st_mtime, str(path.relative_to(staging_dir)).lower()),
     )
     if not files:
         raise RuntimeError("No downloaded files were found in the staging folder")
@@ -1103,10 +1118,7 @@ def finalize_library_files(job):
         shutil.move(str(source), str(destination))
         moved.append(str(destination))
 
-    try:
-        staging_dir.rmdir()
-    except OSError:
-        pass
+    shutil.rmtree(staging_dir, ignore_errors=True)
     return moved
 
 
@@ -1153,7 +1165,26 @@ def build_job(payload, config):
     }
 
 
-def command_for_job(job):
+def anipy_search_spec(job):
+    query = re.sub(r"\s+", " ", str(job.get("query") or "").replace(":", " ")).strip()
+    mode = "dub" if str(job.get("mode") or "").strip().lower() == "dub" else "sub"
+    return f"{query}:{job['episodes']}:{mode}"
+
+
+def command_for_job(job, backend="ani-cli", download_path=None):
+    normalized_backend = str(backend or "ani-cli").strip().lower()
+    if normalized_backend == "anipy-cli":
+        command = [
+            ANIPY_CLI,
+            "-D",
+            "-s",
+            anipy_search_spec(job),
+            "-q",
+            job["quality"],
+        ]
+        if download_path:
+            command.extend(["-l", str(download_path)])
+        return command
     command = [
         ANI_CLI,
         "-d",