chore: adopt MPL-2.0 and complete distribution notices

[jacksteamdev]

Astrology Engine now uses MPL-2.0 for its own source, tools and example adapters. Package metadata, source headers, the project license and copyright notice agree. Existing third-party terms and attribution remain intact, including the full Astronomy Engine MIT notice in adapted files.

Distributions now carry complete notices for the locked dependency graphs, including MPL source links, SOFA terms, math-library attribution and the Rust standard library. Native, Worker and browser builds also package an editable first-party source archive and link it from the notices page. The browser build rebuilds Wasm before packaging so the binary and source snapshot match. The Cargo source package includes the license and notices.

Pinned notice generation and CI reject stale bundles, unreviewed dependency sources and missing license material. The repository remains private; this PR does not publish a release or change visibility.

Validation:

• Nine notice tests, strict TypeScript, deterministic notice regeneration and Rust formatting pass.
• Native release packaging, both Worker build modes, browser Wasm/static build and Cargo package verification pass.
• Artifact source archives match the current source files byte for byte; required notices are present.
• Local Worker structural/adapter harness, prohibition-hook tests and runtime-boundary checks pass.
• Standards and spec reviews have no remaining findings. Runtime calculations and fixture contents are unchanged.