fix: align quickstart with d0a1.es ecosystem and current reality

Hardening pass over the quickstart repo to make it match the actual
d0a1.es stack and remove long-standing drift.

- README: align with 8 GB RAM reality across all sections, add
  explicit security warning on WEBUI_AUTH=false, remove dead link
  to d0a1.es/vps, drop stack services not part of d0a1.es
  (n8n, WordPress, Qdrant). Re-point the d0a1 section to the
  services that actually run at git/mail/app.d0a1.es.
- docker-compose: move all tunables (ports, default model, auth,
  secret key, keep-alive) to .env with sensible defaults. Add
  commented GPU passthrough block for NVIDIA hosts.
- deploy.sh: pre-flight checks (docker, compose, daemon),
  copy .env.example on first run, auto-detect system RAM on
  Linux and macOS and warn on sub-8 GB hosts.
- Add .env.example documenting every variable and required RAM
  per model.
- Add MIT LICENSE (was promised in README but missing).
- Add .gitignore (local .env, editor cruft, OS junk).
- .gitattributes: use a single rule (text=auto eol=lf) to cover
  every text file, not just *.sh - fixes CRLF warnings on new
  text files on Windows checkouts.

Refs: d0a1/quickstart rename (companion: new repo at
git.d0a1.es/d0a1/quickstart).

.gitattributes

@@ -1,10 +1,10 @@
-# Garantiza que los scripts se guarden con saltos de línea Unix (LF),
-# incluso en clones desde Windows. Evita que `bash deploy.sh` rompa
-# con errores tipo "$'\r': command not found" en WSL / Git Bash.
-*.sh        text eol=lf
-*.bash      text eol=lf
+# Normaliza todos los archivos de texto a LF en checkout/merge
+# para evitar problemas con deploy.sh en WSL/Git Bash.
+* text=auto eol=lf
 
-# Documentación también en LF para consistencia.
-*.md        text eol=lf
-*.yml       text eol=lf
-*.yaml      text eol=lf
+# Tratar como binarios
+*.png binary
+*.jpg binary
+*.ico binary
+*.msi binary
+*.pdf binary