Move readme to rust docs

[oflatt]

No description provided.

[Copilot]

Pull request overview

This PR prepares the egglog-experimental crate for its 1.0 release by bumping the version from 0.1.0 to 1.0.0, adding essential package metadata for crates.io publication, consolidating documentation into the crate-level docs, and making the rational module public.

• Version updated from 0.1.0 to 1.0.0 across Cargo.toml and Cargo.lock
• Added crates.io metadata (description, repository, keywords, license, readme)
• Moved "Implemented extensions" documentation from README.md to src/lib.rs crate docs
• Changed rational module visibility from private to public

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.

File	Description
Cargo.toml	Bumped version to 1.0.0, added edition field, and included crates.io metadata (description, repository, keywords, license, readme)
Cargo.lock	Updated version to 1.0.0 to match Cargo.toml
README.md	Removed "Implemented extensions" section, replaced with link to docs.rs documentation
src/lib.rs	Added comprehensive crate-level documentation including all implemented extensions with demo links, made rational module public

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[yihozhang]

To release egglog-experimental, we need to first cut a release for egglog (which will be versioned at v2.0.0 because we introduced a breaking change to egglog soon after the release, AFAIR). So egglog-experimental will also likely to be versioned at 2.0.0

[oflatt]

Hmm I feel like we are not ready for 2.0 yet, but I also want to release this so docs are available.