feat: cosmos standalone — motor astrométrico/astrológico sobre Llimphi (git-dep al monorepo)

Efemérides + cielo + reloj de sol + mareas + tránsitos + apuntado, más motor
de cartas y UI GPU (app + canvas, demo dense_starfield vía pineal). Front-door:
solo crates cosmos-*; Llimphi y lo fundacional por git-dep del monorepo
gioser.git. cargo check pasa (31 crates, 0 errores).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

README.md

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+# cosmos
+
+> Pure astrometry + astrology engine — ephemeris, sky, sundial, tides, transits — in Rust, with a [Llimphi](https://gitea.gioser.net/sergio/llimphi) UI.
+
+`cosmos` computes the sky. Around a core astrology engine sit independent astrometric extracts — `cosmos-ephemeris`, `cosmos-sky`, `cosmos-sundial`, `cosmos-tides`, `cosmos-transits`, `cosmos-pointing` — that serve sundial / tides / navigation / planning without touching the chart machinery. A GPU UI (`cosmos-app-llimphi`, `cosmos-canvas-llimphi`) renders charts, sky maps and a dense starfield.
+
+## Run
+
+```sh
+cargo run --release -p cosmos-app-llimphi              # the chart/sky desktop app
+cargo run --release -p cosmos-canvas-llimphi --example dense_starfield
+```
+
+## How dependencies work
+
+cosmos is a full app: its UI integrates notebooks, panels and content-addressed sources. Llimphi and every foundational dependency are pulled as git dependencies from the [`gioser`](https://gitea.gioser.net/sergio/gioser) monorepo — the suite's source of truth. The astrometric core crates (`cosmos-ephemeris`, `-coords`, `-time`, …) are pure compute with no UI deps.
+
+## License
+
+MIT. Builds on [Llimphi](https://gitea.gioser.net/sergio/llimphi) and the [gioser](https://gitea.gioser.net/sergio/gioser) suite.