Restore f1-stream stack — undo accidental bundling into 63fe7d2b

Commit 63fe7d2b (fan-control) was made with a bare `git commit` in the
shared infra working tree and inadvertently swept in a parallel session's
staged f1-stream-extraction work (main.tf repoint, ~48 files/ removals,
ci-cd.md + .claude docs, two extraction plan docs).

This returns every f1-stream-related path to its pre-63fe7d2b state
(3493c347) so that extraction can be committed cleanly by its own
session. The fan-control files added in 63fe7d2b are untouched.

[ci skip]

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

stacks/f1-stream/files/backend/extractors/demo.py

@@ -0,0 +1,75 @@
+"""Demo extractor - returns hardcoded test streams for framework testing.
+
+This extractor exists purely for testing the extraction pipeline end-to-end.
+It does NOT connect to any real streaming site. Disable it in production by
+removing its registration from __init__.py or setting DEMO_EXTRACTOR_ENABLED=false.
+"""
+
+import logging
+import os
+
+from backend.extractors.base import BaseExtractor
+from backend.extractors.models import ExtractedStream
+
+logger = logging.getLogger(__name__)
+
+# Set DEMO_EXTRACTOR_ENABLED=false to disable this extractor
+DEMO_ENABLED = os.getenv("DEMO_EXTRACTOR_ENABLED", "true").lower() in ("true", "1", "yes")
+
+
+class DemoExtractor(BaseExtractor):
+    """Demo extractor that returns hardcoded test streams.
+
+    Use this to verify the extraction framework works end-to-end without
+    needing a real streaming site. The streams are publicly available HLS
+    test streams from Apple and others.
+    """
+
+    @property
+    def site_key(self) -> str:
+        return "demo"
+
+    @property
+    def site_name(self) -> str:
+        return "Demo (Test Streams)"
+
+    async def extract(self) -> list[ExtractedStream]:
+        """Return hardcoded test streams for framework testing."""
+        if not DEMO_ENABLED:
+            logger.info("[demo] Demo extractor is disabled via DEMO_EXTRACTOR_ENABLED")
+            return []
+
+        logger.info("[demo] Returning demo test streams")
+
+        streams = [
+            ExtractedStream(
+                url="https://test-streams.mux.dev/x36xhzz/x36xhzz.m3u8",
+                site_key=self.site_key,
+                site_name=self.site_name,
+                quality="720p",
+                title="Big Buck Bunny (Test Stream)",
+                is_live=False,
+            ),
+            ExtractedStream(
+                url="https://devstreaming-cdn.apple.com/videos/streaming/examples/bipbop_16x9/bipbop_16x9_variant.m3u8",
+                site_key=self.site_key,
+                site_name=self.site_name,
+                quality="1080p",
+                title="Apple Bipbop (Test Stream)",
+                is_live=False,
+            ),
+            ExtractedStream(
+                url="https://demo.unified-streaming.com/k8s/features/stable/video/tears-of-steel/tears-of-steel.ism/.m3u8",
+                site_key=self.site_key,
+                site_name=self.site_name,
+                quality="1080p",
+                title="Tears of Steel (Test Stream)",
+                is_live=False,
+            ),
+        ]
+
+        # Optionally run health checks on the demo streams
+        for stream in streams:
+            stream.is_live = await self.health_check(stream.url)
+
+        return streams