feat(providers): add a pluggable station-catalogue seam

The app now holds one RadioProvider and asks it for stations, song history and stream URLs instead of importing SomaFM's HTTP client directly.

- models.py: provider-neutral Song/Station plus the shared parsers every catalogue needs (Station.provider/.uid keep ids unique once there is more than one).
- providers/base.py: the RadioProvider interface and the toolkit it needs in practice - httpx client factory, .pls/.m3u resolution with an 8h disk cache, and a default stream_candidates() strategy.
- providers/somafm/: everything SomaFM-specific (channels.json, songs/<id>.json, PLS layout, guessed icecast mirrors) behind SomaFMProvider.
- providers/__init__.py: registry, get_provider() and --provider, remembered in the config file.

Widgets render branding, splash copy and the help credits from the active provider, so a second catalogue needs no UI changes; with SomaFM selected the screen is byte-identical to before.

beefy_player/widgets/help.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 
 import sys
 import textwrap
+from typing import TYPE_CHECKING, cast
 
 from rich.console import Group
 from rich.table import Table
@@ -14,6 +15,9 @@ from textual.widgets import Static
 
 from .common import SPECTRUM_STOPS, gradient
 
+if TYPE_CHECKING:
+    from ..app import BeefyPlayerApp
+
 HELP_ROWS: tuple[tuple[str, str], ...] = (
     ("↑ / ↓  j / k", "move through the station list"),
     ("enter", "tune in to the selected station"),
@@ -35,13 +39,6 @@ HELP_ROWS: tuple[tuple[str, str], ...] = (
     ("q", "quit"),
 )
 
-ABOUT_COMMON = (
-    (
-        "Stations and song history come from somafm.com "
-        "(channels.json + songs/<station>.json)."
-    ),
-)
-
 ABOUT_LINUX = (
     (
         "The spectrum captures your actual PulseAudio/PipeWire output with "
@@ -50,7 +47,7 @@ ABOUT_LINUX = (
     ),
     (
         "The desktop picks us up over MPRIS as a "
-        "somafmtui media player — try `playerctl -l` / `playerctl metadata`."
+        "beefyplayer media player — try `playerctl -l` / `playerctl metadata`."
     ),
 )
 
@@ -68,11 +65,15 @@ ABOUT_MACOS = (
     ),
 )
 
-ABOUT = ABOUT_COMMON + (ABOUT_MACOS if sys.platform == "darwin" else ABOUT_LINUX)
-
 
 class HelpScreen(ModalScreen[None]):
     def compose(self) -> ComposeResult:
+        provider = cast("BeefyPlayerApp", self.app).provider
+        about = (
+            f"Stations and song history come from {provider.name} "
+            f"({provider.station_source} + {provider.history_source}).",
+        ) + (ABOUT_MACOS if sys.platform == "darwin" else ABOUT_LINUX)
+
         table = Table.grid(padding=(0, 2), expand=False)
         table.add_column(style="bold cyan", no_wrap=True, justify="right")
         table.add_column(style="")
@@ -81,11 +82,11 @@ class HelpScreen(ModalScreen[None]):
 
         header = Text()
         header.append("◤ ", style=f"bold {gradient(SPECTRUM_STOPS, 0.9)}")
-        header.append("SOMAFM TUI", style=f"bold {gradient(SPECTRUM_STOPS, 0.55)}")
+        header.append("BEEFY PLAYER", style=f"bold {gradient(SPECTRUM_STOPS, 0.55)}")
         header.append("  keyboard & credits", style="dim")
 
         footer = Text()
-        for paragraph in ABOUT:
+        for paragraph in about:
             for line in textwrap.wrap(paragraph, width=70):
                 footer.append(line + "\n", style="dim")
 

beefy_player/widgets/stage.py

@@ -11,7 +11,7 @@ from textual.containers import Horizontal
 from textual.css.query import NoMatches
 from textual.widget import Widget
 
-from ..api import Song, Station
+from ..models import Song, Station
 from .art import ArtPane
 from .common import (
     compact_count,
@@ -23,7 +23,7 @@ from .common import (
 )
 
 if TYPE_CHECKING:
-    from ..app import SomaFMApp
+    from ..app import BeefyPlayerApp
 
 
 class StagePanel(Widget):
@@ -75,27 +75,30 @@ class StageInfo(Widget):
     can_focus = False
 
     def render(self) -> RenderableType:
-        app = cast("SomaFMApp", self.app)
+        app = cast("BeefyPlayerApp", self.app)
         width = max(8, self.size.width)
         height = max(1, self.size.height)
         station = app.current
 
         if station is None:
-            return Group(*self._splash(width, height))
+            return Group(*self._splash(app, width, height))
 
         details = self._details(app, station, station.now_playing, width)
         return Group(*details[:height])
 
-    def _splash(self, width: int, height: int) -> list[Text]:
+    def _splash(
+        self, app: BeefyPlayerApp, width: int, height: int
+    ) -> list[Text]:
+        provider = app.provider
         lines = [
-            Text("◤ SOMA FM ◢", style="bold magenta"),
-            Text("listener-supported radio · san francisco", style="italic dim"),
+            Text(f"◤ {provider.brand} ◢", style="bold magenta"),
+            Text(provider.tagline, style="italic dim"),
             Text(""),
             Text("↑ ↓  choose a station", style=""),
             Text("⏎    tune in", style=""),
             Text("?    all keyboard shortcuts", style=""),
             Text(""),
-            Text("Stations load from somafm.com/channels.json", style="dim"),
+            Text(f"Stations load from {provider.station_source}", style="dim"),
         ]
         return [
             Text(truncate(line.plain, width), style=line.style)
@@ -104,7 +107,7 @@ class StageInfo(Widget):
 
     def _details(
         self,
-        app: SomaFMApp,
+        app: BeefyPlayerApp,
         station: Station,
         song: Song | None,
         width: int,
@@ -188,7 +191,7 @@ class HistoryPane(Widget):
     can_focus = False
 
     def render(self) -> RenderableType:
-        app = cast("SomaFMApp", self.app)
+        app = cast("BeefyPlayerApp", self.app)
         width = max(8, self.size.width)
         height = max(1, self.size.height)
         station = app.current