Enhance GPU flavor scanning and update documentation

- Introduced SCAN_POOLS configuration to specify pools for GPU flavor scanning.
- Updated the `flavors` command to scan specified pools and list available GPU flavors based on `FLAVOR_PREFERENCE`.
- Revised CLI documentation to reflect changes in the `flavors` command behavior.
- Enhanced decision documentation to include details about GPU pool scanning.
- Updated setup instructions to guide users on selecting appropriate GPU pools.

src/gpu_rent/cli.py

@@ -153,14 +153,25 @@ def dry_run() -> None:
 
 
 @app.command()
-def flavors() -> None:
-    """Живой список GPU flavors по FLAVOR_PREFERENCE."""
+def flavors(
+    scan: bool = typer.Option(True, "--scan/--no-scan", help="Скан пулов SCAN_POOLS (ru-6 multizone…)"),
+) -> None:
+    """GPU flavors: скан пулов + список в текущем OS_REGION_NAME."""
     try:
         from gpu_rent.inventory import looks_like_gpu, rank_flavors, resolve_flavor
         from gpu_rent.os_client import iter_flavors
+        from gpu_rent.pools import format_pool_scan, scan_pools
         from gpu_rent.ux import format_flavor_lines
 
         cfg = load_config(require_auth=True)
+        if scan:
+            console.print(f"[bold]region сейчас[/bold]: {cfg.os_region_name} / AZ {cfg.gpu_rent_az}")
+            console.print(f"[bold]SCAN_POOLS[/bold]: {cfg.scan_pools or 'ru-6,ru-7'}")
+            offers = scan_pools(cfg)
+            for line in format_pool_scan(offers, cfg.flavor_preference):
+                console.print(line)
+            console.print("")
+
         conn = connect(cfg)
         all_f = list(iter_flavors(conn))
         gpu = [f for f in all_f if looks_like_gpu(f)]
@@ -174,13 +185,14 @@ def flavors() -> None:
             )
         except ValueError:
             picked = None
+        console.print(f"[bold]в пуле {cfg.os_region_name}[/bold] (то, что возьмёт up):")
         for line in format_flavor_lines(ranked, picked):
             console.print(line)
         console.print(
             f"\nspot по умолчанию: {cfg.default_spot}  "
             f"(обычный: gpu-rent up --no-spot)"
         )
-        console.print("₽ в API нет — смотри панель Selectel.")
+        console.print("₽ в API нет — смотри панель. Серые кнопки панели ≠ disabled в Nova.")
     except GpuRentError as exc:
         _die(exc)