fix(deps): declare youtube-transcript-api in pyproject.toml [youtube] extra

skills/media/youtube-content/scripts/fetch_transcript.py and
optional-skills/productivity/memento-flashcards/scripts/youtube_quiz.py
both import youtube-transcript-api at runtime, but the package was not
listed in pyproject.toml.  A fresh `uv sync` therefore omits it, and
both skills fail on first invocation with:

    ModuleNotFoundError: No module named 'youtube_transcript_api'

Add a new [youtube] optional-dependency group with
youtube-transcript-api>=1.2.0 (the v1.x API surface the scripts already
use) and include it in [all] so standard installs pick it up.

Regression tests: TestPyprojectDeclaresYoutubeExtra verifies the extra
is present in pyproject.toml and included in [all].

Closes #22243

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -126,6 +126,13 @@ google = [
   "google-auth-oauthlib>=1.0,<2",
   "google-auth-httplib2>=0.2,<1",
 ]
+youtube = [
+  # Required by skills/media/youtube-content and
+  # optional-skills/productivity/memento-flashcards (youtube_quiz.py).
+  # Without this declaration uv sync omits the package and both skills fail
+  # at first invocation with ModuleNotFoundError (issue #22243).
+  "youtube-transcript-api>=1.2.0",
+]
 # `hermes dashboard` (localhost SPA + API).  Not in core to keep the default install lean.
 web = ["fastapi>=0.104.0,<1", "uvicorn[standard]>=0.24.0,<1"]
 rl = [
@@ -163,6 +170,7 @@ all = [
   "hermes-agent[mistral]",
   "hermes-agent[bedrock]",
   "hermes-agent[web]",
+  "hermes-agent[youtube]",
 ]
 
 [project.scripts]

tests/skills/test_fetch_transcript.py

@@ -0,0 +1,87 @@
+"""Tests for skills/media/youtube-content/scripts/fetch_transcript.py (issue #22243)."""
+
+import sys
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+SCRIPTS_DIR = Path(__file__).resolve().parents[2] / "skills" / "media" / "youtube-content" / "scripts"
+sys.path.insert(0, str(SCRIPTS_DIR))
+
+import fetch_transcript
+
+
+class TestExtractVideoId:
+    def test_standard_watch_url(self):
+        assert fetch_transcript.extract_video_id("https://www.youtube.com/watch?v=dQw4w9WgXcQ") == "dQw4w9WgXcQ"
+
+    def test_short_url(self):
+        assert fetch_transcript.extract_video_id("https://youtu.be/dQw4w9WgXcQ") == "dQw4w9WgXcQ"
+
+    def test_bare_video_id(self):
+        assert fetch_transcript.extract_video_id("dQw4w9WgXcQ") == "dQw4w9WgXcQ"
+
+    def test_shorts_url(self):
+        assert fetch_transcript.extract_video_id("https://www.youtube.com/shorts/dQw4w9WgXcQ") == "dQw4w9WgXcQ"
+
+    def test_embed_url(self):
+        assert fetch_transcript.extract_video_id("https://www.youtube.com/embed/dQw4w9WgXcQ") == "dQw4w9WgXcQ"
+
+    def test_with_extra_params(self):
+        assert fetch_transcript.extract_video_id("https://www.youtube.com/watch?v=dQw4w9WgXcQ&t=42") == "dQw4w9WgXcQ"
+
+
+class TestFormatTimestamp:
+    def test_seconds_only(self):
+        assert fetch_transcript.format_timestamp(90) == "1:30"
+
+    def test_with_hours(self):
+        assert fetch_transcript.format_timestamp(3661) == "1:01:01"
+
+    def test_zero(self):
+        assert fetch_transcript.format_timestamp(0) == "0:00"
+
+    def test_minutes_only(self):
+        assert fetch_transcript.format_timestamp(600) == "10:00"
+
+
+class TestFetchTranscriptImportError:
+    def test_missing_dep_exits_with_message(self, capsys):
+        """fetch_transcript exits with code 1 and prints install hint when package missing (issue #22243)."""
+        import builtins
+        real_import = builtins.__import__
+
+        def mock_import(name, *args, **kwargs):
+            if name == "youtube_transcript_api":
+                raise ImportError("No module named 'youtube_transcript_api'")
+            return real_import(name, *args, **kwargs)
+
+        with mock.patch("builtins.__import__", side_effect=mock_import):
+            with pytest.raises(SystemExit) as exc_info:
+                fetch_transcript.fetch_transcript("dQw4w9WgXcQ")
+        assert exc_info.value.code == 1
+        captured = capsys.readouterr()
+        assert "youtube-transcript-api" in captured.err
+
+
+class TestPyprojectDeclaresYoutubeExtra:
+    def test_youtube_extra_declared_in_pyproject(self):
+        """youtube-transcript-api must be listed in pyproject.toml [youtube] extra (issue #22243)."""
+        import tomllib
+        pyproject_path = Path(__file__).resolve().parents[2] / "pyproject.toml"
+        with pyproject_path.open("rb") as f:
+            data = tomllib.load(f)
+        extras = data.get("project", {}).get("optional-dependencies", {})
+        assert "youtube" in extras, "Missing [youtube] extra in pyproject.toml"
+        youtube_deps = " ".join(extras["youtube"])
+        assert "youtube-transcript-api" in youtube_deps
+
+    def test_youtube_extra_included_in_all(self):
+        """[all] extra must include hermes-agent[youtube] (issue #22243)."""
+        import tomllib
+        pyproject_path = Path(__file__).resolve().parents[2] / "pyproject.toml"
+        with pyproject_path.open("rb") as f:
+            data = tomllib.load(f)
+        all_deps = " ".join(data["project"]["optional-dependencies"].get("all", []))
+        assert "youtube" in all_deps, "[all] extra does not include hermes-agent[youtube]"