Jellyflow 0.1.0

Initial public release line for Jellyflow. This release establishes the headless graph engine,
adapter boundary, layout extension point, release documentation, and crates.io automation.

Added

• Added the top-level jellyflow facade crate. It re-exports jellyflow-core,
  jellyflow-layout, and jellyflow-runtime under core, layout, and runtime, and provides a
  small prelude for common graph-store setup.
• Added release-facing README guidance modeled after a published Rust workspace: entry-point
  selection, install commands, quickstarts, adapter conformance, performance, quality gates, and
  workspace crate roles.
• Added release CI workflows for manual crates.io preflight checks, dependency-ordered publishing,
  and GitHub Release creation.
• Added external consumer smoke coverage for applications that depend on the top-level
  jellyflow facade crate.
• Added runtime benchmark smoke coverage for rendering_query and schema_create_node.

Changed

• Updated crates.io publishing documentation for the four-crate release order:
  jellyflow-core, jellyflow-layout, jellyflow-runtime, then jellyflow.
• Expanded dependency-boundary checks so all publishable crates reject accidental fret or
  fret-* dependencies.
• Committed the workspace Cargo.lock and aligned CI/tooling with Rust 1.95.
• Updated the headless adapter template to use the workspace MSRV.

Fixed

• Fixed CI locked-check failures by committing the workspace lockfile and keeping the root
  Cargo.lock unignored.