Рабочий пайплайн: YouTube -> транскрипция -> выжимка -> Postgres

- новый api/: /pipeline/process (yt-dlp, субтитры или Vosk, LLM/экстрактивная
  суммаризация), /videos, /llm; старый код перенесён в api_legacy/
- web/: Flet UI (flet 0.28.3 + flet-web, порт 8550)
- Dockerfile.api: ffmpeg слоем из mwader/static-ffmpeg, pip с кэш-маунтом
- requirements/pyproject: убраны moviepy, imageio-ffmpeg, битый asyncio
- README с инструкцией запуска и загрузкой Vosk-модели

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

api_legacy/config.py

@@ -0,0 +1,28 @@
+from pydantic_settings import BaseSettings
+import os
+
+def _env(*names, default=None):
+    for n in names:
+        v = os.getenv(n)
+        if v:
+            return v
+    return default
+
+class Settings(BaseSettings):
+    # support both custom DB_* names and common POSTGRES_* names from postgres images
+    DB_USER: str = _env("DB_USER", "POSTGRES_USER", default="postgres")
+    DB_PASS: str = _env("DB_PASS", "POSTGRES_PASSWORD", default="postgres")
+    DB_NAME: str = _env("DB_NAME", "POSTGRES_DB", default="test_db")
+    DB_HOST: str = _env("DB_HOST", "POSTGRES_HOST", "DB_HOST", default="db")
+    DB_PORT: str = _env("DB_PORT", "POSTGRES_PORT", default="5432")
+
+    # If explicit DB_* variables are provided, build DATABASE_URL from them (priority).
+    # Otherwise fall back to explicit DATABASE_URL or DATABASE_URL_ASYNC env.
+    _built_db_url: str | None = None
+    if DB_USER and DB_PASS and DB_NAME and DB_HOST and DB_PORT:
+        _built_db_url = f"postgresql+asyncpg://{DB_USER}:{DB_PASS}@{DB_HOST}:{DB_PORT}/{DB_NAME}"
+
+    DATABASE_URL: str = _built_db_url or _env("DATABASE_URL", "DATABASE_URL_ASYNC", default="")
+
+
+settings = Settings()