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/notes/08-descriptive-adjectives.md

@@ -0,0 +1,63 @@
+# 08. Descriptive Adjectives
+
+> Source: [A Complete Guide To Every Fundamental In Spanish](https://youtube.com/watch?v=YHDZSHCt1DE&t=1948s)
+
+Descriptive adjectives in Spanish describe a person or thing physically or by condition. Unlike English, Spanish adjectives must agree with the noun in gender and number, and they normally come *after* the noun.
+
+## Key Rules
+- Adjectives ending in **-o** are masculine; **-a** are feminine; some end in **-e** or a consonant and are neutral (use the same form for both genders).
+- Add **-s** (or **-es** after a consonant) to pluralize: `fácil → fáciles`, `feo → feos`.
+- Adjectives normally come **after** the noun: `el chico inteligente`, *not* `el inteligente chico`.
+- Use **ser** for permanent/factual traits (alto, bonito, inteligente).
+- Use **estar** for temporary states/conditions (cansado, triste, enfermo, relajado).
+
+## Common Descriptive Adjectives
+
+### With ser (factual / inherent)
+| Adjective | Meaning |
+|-----------|---------|
+| alto/a(s) | tall |
+| bajo/a(s) | short |
+| bonito/a(s) | beautiful |
+| feo/a(s) | ugly |
+| fácil / fáciles | easy |
+| difícil / difíciles | difficult |
+| importante(s) | important |
+| inteligente(s) | intelligent / smart |
+
+### With estar (condition / emotion)
+| Adjective | Meaning |
+|-----------|---------|
+| aburrido/a(s) | bored |
+| cansado/a(s) | tired |
+| enfermo/a(s) | sick |
+| listo/a(s) | ready |
+| seguro/a(s) | sure |
+| preparado/a(s) | prepared |
+| relajado/a(s) | relaxed |
+| triste(s) | sad |
+
+## Examples
+| Spanish | English |
+|---------|---------|
+| Yo soy alto y bonito. | I am tall and handsome. (m) |
+| Yo soy alta y bonita. | I am tall and beautiful. (f) |
+| Ellos son feos. | They are ugly. (m) |
+| Estas clases son fáciles. | These classes are easy. |
+| Nosotros somos inteligentes. | We are intelligent. |
+| El chico es inteligente. | The boy is smart. |
+| El chico inteligente. | The smart boy. |
+| Este video importante. | This important video. |
+| La lección difícil. | The difficult lesson. |
+| Yo soy bajo. | I am short. (factual trait → ser) |
+| Yo estoy cansado. | I am tired. (changing condition → estar) |
+| La chica hermosa / La chica es hermosa. | The beautiful girl / The girl is beautiful. |
+| El hombre relajado / El hombre está relajado. | The relaxed man / The man is relaxed. |
+| Él es inteligente. | He is smart. |
+| Nosotros estamos tristes. | We are sad. |
+
+## Notes & Gotchas
+- Word order is the #1 mistake for English speakers — adjective goes **after** the noun.
+- Some adjectives change meaning depending on ser vs estar (e.g., `ser listo` = clever; `estar listo` = ready).
+- Neutral-ending adjectives (-e, consonant) don't change for gender, but still pluralize.
+- Always make number/gender agree across the *whole* phrase: `nosotros estamos tristes` (plural subject → plural adjective).