feat: local content-mining platform for YouTube creator scraping

Scraper de canales de YouTube hacia notas Markdown para base de conocimiento
(Obsidian-ready), con plataforma web local.

Engine + CLI (Workstream A):
- Modular pipeline: discover/extract/parse/chapters/render/store + ratelimit
- SQLite store con migración idempotente: FTS5 (transcript search), columnas
  de metadata enriquecida, tablas cookies_meta y scrape_jobs
- Módulos: segments, cookies (Netscape vault), export (json/csv/srt/html),
  analysis (word freq/timeline/wordcloud), monitor (watch loop), pipeline
- CLI Click group: search, export, audio, channels, watch, analyze, re-render
- Fix del bug de scoping de cookies en cli.py

Webapp local (Workstream B):
- FastAPI backend: dashboard, channels, videos facetado, transcript, search
  FTS, analysis, scrape jobs con SSE, cookies drag-and-drop, exports,
  folders (abrir en OS), tools (re-render, formato)
- SPA no-build (Alpine.js + Tailwind + Chart.js por CDN): 9 vistas, tema
  dark command-center con acento rojo→rosa, cookie vault drag-drop,
  consola de scrapeo con progreso live vía SSE

Launcher + subagentes (Workstream C):
- start-server.bat / stop-server.bat con auto port-scan + browser open
- .opencode/agent/webapp-builder.md + .opencode/goals/webapp-build.md

Tests: 38 pytest verdes. Sin funcionalidad de IA (enfoque data-mining).

config.example.yaml

@@ -0,0 +1,23 @@
+channel_url: "https://www.youtube.com/@Nostal-Vlad/videos"
+
+languages: ["es", "es-419", "en"]
+prefer_manual: true
+include_shorts: false
+include_live: true
+min_duration_sec: 30
+
+delay:
+  min_seconds: 1.5
+  max_seconds: 3.5
+  backoff_base: 2.0
+  backoff_cap: 60.0
+
+yt_dlp:
+  retries: 10
+  sleep_subrequests: 2
+
+database_path: "data/state.db"
+output_dir: "data/markdown"
+template_path: "templates/video.md.j2"
+
+filename_template: "{upload_date}_{slug}"