Add 13 new grammar notes with 1010 exercises from video extraction

Scraped a 4h Spanish fundamentals YouTube video (transcript + OCR on
14810 frames), extracted structured content across 52 chapters, and
generated fill-in-the-blank quizzes for every grammar topic.

- 13 new GrammarNote entries (articles, possessives, demonstratives,
  greetings, poder, al/del, prepositional pronouns, irregular yo,
  stem-changing, stressed possessives, present/future perfect, present
  indicative conjugation)
- 1010 generated exercises across all 36 grammar notes (new + existing)
- Fix tense guide parser to handle unnumbered *Usages* blocks
- Rewrite 6 broken tense guide bodies (imperative, subj pluperfect,
  subj future) with numbered usage format
- Bump courseDataVersion 5→6 with TenseGuide refresh on upgrade
- Add docs/spanish-fundamentals/ with raw transcripts, polished notes,
  structured JSON, and exercise data

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/spanish-fundamentals/structured/03-conjugating-verbs-present.json

@@ -0,0 +1,76 @@
+{
+  "chapter_id": "03",
+  "slug": "conjugating-verbs-present",
+  "title": "Conjugating Verbs (Present)",
+  "time_range_sec": [632, 983],
+  "summary": "How to conjugate regular -ar/-er/-ir verbs in the present indicative by dropping the infinitive ending and adding one of six person endings.",
+  "suggested_grammar_note_id": null,
+  "rules": [
+    {
+      "title": "Identifying verbs",
+      "bullets": [
+        "English infinitives use 'to' (to eat).",
+        "Spanish infinitives end in -ar, -er, or -ir."
+      ]
+    },
+    {
+      "title": "Conjugation procedure",
+      "bullets": [
+        "Drop the -ar/-er/-ir ending.",
+        "Add the ending that matches the subject pronoun.",
+        "Six endings per tense (one per pronoun)."
+      ]
+    },
+    {
+      "title": "Practical focus",
+      "bullets": [
+        "yo, tú, él, ellos are by far the most-used persons in conversation.",
+        "Subject pronouns are usually omitted because the verb ending tells you who.",
+        "-er and -ir share endings except for nosotros and vosotros."
+      ]
+    }
+  ],
+  "examples": [
+    {"es": "Yo hablo español.", "en": "I speak Spanish.", "tags": ["hablar"]},
+    {"es": "Tú hablas mucho.", "en": "You talk a lot.", "tags": ["hablar"]},
+    {"es": "Ella habla con su madre.", "en": "She talks with her mother.", "tags": ["hablar"]},
+    {"es": "Nosotros hablamos inglés.", "en": "We speak English.", "tags": ["hablar"]},
+    {"es": "Yo como pizza.", "en": "I eat pizza.", "tags": ["comer"]},
+    {"es": "Comemos en casa.", "en": "We eat at home.", "tags": ["comer"]},
+    {"es": "Ellos comen tacos.", "en": "They eat tacos.", "tags": ["comer"]},
+    {"es": "Yo vivo en Madrid.", "en": "I live in Madrid.", "tags": ["vivir"]},
+    {"es": "Tú vives cerca.", "en": "You live nearby.", "tags": ["vivir"]},
+    {"es": "Ellos viven juntos.", "en": "They live together.", "tags": ["vivir"]}
+  ],
+  "vocab": [
+    {"es": "hablar", "en": "to speak", "pos": "verb"},
+    {"es": "comer", "en": "to eat", "pos": "verb"},
+    {"es": "vivir", "en": "to live", "pos": "verb"}
+  ],
+  "conjugation_tables": [
+    {
+      "verb": "hablar",
+      "tense_id": "ind_presente",
+      "forms": {"yo": "hablo", "tu": "hablas", "el": "habla", "nosotros": "hablamos", "vosotros": "habláis", "ellos": "hablan"}
+    },
+    {
+      "verb": "comer",
+      "tense_id": "ind_presente",
+      "forms": {"yo": "como", "tu": "comes", "el": "come", "nosotros": "comemos", "vosotros": "coméis", "ellos": "comen"}
+    },
+    {
+      "verb": "vivir",
+      "tense_id": "ind_presente",
+      "forms": {"yo": "vivo", "tu": "vives", "el": "vive", "nosotros": "vivimos", "vosotros": "vivís", "ellos": "viven"}
+    }
+  ],
+  "exercises": [
+    {"sentence": "Yo _____ español todos los días.", "correct": "hablo", "distractor": "hablas", "explanation": "yo takes -o in -ar verbs: hablo."},
+    {"sentence": "Tú _____ pizza los viernes.", "correct": "comes", "distractor": "comen", "explanation": "tú takes -es in -er verbs: comes."},
+    {"sentence": "Nosotros _____ en Madrid.", "correct": "vivimos", "distractor": "vivís", "explanation": "nosotros + -ir = -imos."},
+    {"sentence": "Ellos _____ con sus amigos.", "correct": "hablan", "distractor": "habla", "explanation": "ellos + -ar = -an."},
+    {"sentence": "Ella _____ mucho café.", "correct": "come", "distractor": "como", "explanation": "ella + -er = -e (like the él form)."},
+    {"sentence": "Yo _____ cerca de la escuela.", "correct": "vivo", "distractor": "vive", "explanation": "yo + -ir = -o."}
+  ],
+  "caveats": null
+}