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/50-present-perfect-subjunctive.md

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+# 50. Present Perfect Subjunctive
+
+> Source: [A Complete Guide To Every Fundamental In Spanish](https://youtube.com/watch?v=YHDZSHCt1DE&t=14313s)
+
+The present perfect subjunctive expresses what someone *has done* or what *has happened*, in the subjunctive form. It uses the present subjunctive of `haber` (`haya`, `hayas`, `haya`, `hayamos`, `hayáis`, `hayan`) plus a past participle, and is triggered by the same W.E.I.R.D. conditions as the regular present subjunctive.
+
+## Key Rules
+
+- Form: **present subjunctive of `haber` + past participle**.
+- The whole sentence must stay in the **present** — main clause in present indicative, subordinate clause in present perfect subjunctive.
+- Same W.E.I.R.D. triggers as the present subjunctive.
+- `haber + past participle` is **inseparable**: negatives and object pronouns go **before** `haya`.
+- One of the least-used subjunctives — more useful to recognize than to actively produce.
+
+## Conjugation / Pattern Tables
+
+### Auxiliary `haber` (present subjunctive)
+
+| Pronoun | Form |
+|---|---|
+| yo | haya |
+| tú | hayas |
+| él/ella | haya |
+| nosotros | hayamos |
+| vosotros | hayáis |
+| ellos | hayan |
+
+### Pattern
+
+`haya / hayas / haya / hayamos / hayáis / hayan` + past participle (`hablado`, `comido`, `vivido`, `dicho`, `hecho`, `escrito`, `visto`, `resuelto`, `dado`, `pasado`, `venido`, `estudiado`, `dormido`).
+
+## Examples
+
+| Spanish | English |
+|---|---|
+| Yo espero que tú hayas dormido bien. | I hope that you have slept well. |
+| Yo estoy feliz de que él haya dicho la verdad. | I am happy that he has told the truth. |
+| No creemos que tú hayas comido mucho. | We don't believe that you have eaten a lot. |
+| Es posible que hayamos hecho algo malo. | It's possible that we have done something bad. |
+| Es imposible que ellos hayan escrito un libro. | It's impossible that they have written a book. |
+| Yo espero que tú hayas resuelto el problema. | I hope that you have resolved the problem. |
+| Tú esperas que él haya estudiado para la prueba. | You hope that he has studied for the test. |
+| Es triste que él no lo haya pasado. | It's sad that he has not passed it. |
+| Ella duda que hayamos venido tan rápido. | She doubts that we have come so fast. |
+| Ellos están preocupados de que tú los hayas visto. | They are worried that you have seen them. |
+| Es una lástima que ellos no me lo hayan dado. | It's a shame that they have not given it to me. |
+
+## Notes & Gotchas
+
+- Both clauses must be present; mixing tenses kills the trigger (`Yo espero que tú dormiste bien` is ungrammatical — must be `hayas dormido`).
+- Negatives + object pronouns stack **before** `haya`: `no me lo hayan dado`.
+- Common irregular past participles to memorize: `dicho` (decir), `hecho` (hacer), `escrito` (escribir), `visto` (ver), `puesto` (poner), `vuelto` (volver), `resuelto` (resolver), `roto` (romper), `abierto` (abrir).