Update README.md - #32

* docs: release notes and version scoping for v1.3.0

CHANGELOG 1.3.0: confirmed-bar admission in pineforge-live (#342), the Pine
adapter changes of #341, #345 and #347, tests and docs (#343, #344); no
report key changes; the state-hash recipe additions of #341 and #347, domain
tags and the v19 epoch unchanged; migration.

Version scoping: README, install.md and public-contract.md name v1.3.0, its
tarballs, the engine1.3.0-codegen1.3.0 image and the 1.3.0 pair. The
confirmed-bar receipt and its admission, marked unreleased after 1.2.0 by
#342, ship in 1.3.0 (README, strategy-capabilities.md, runner/README.md).

Codegen license lines (README, LEGAL.md, docs/pages/index.md): the PineForge
Source License 1.2 from codegen 1.3.0; 1.2.0 keeps 1.1, releases up to 1.1.0
the PolyForm Noncommercial terms.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

* docs: release 1.3.0's grades in the README and the changelog, from the facts tokens

The README's release sentence moves to the releases[1.3.0] tokens, and its
main-scoreboard lines re-render the values defe41f (#343) rendered at
pineforge-release 3e39d64, and the 1.3.0 changelog says which registry
baseline grades the release and why that baseline is the release's code,
all rendered from pineforge-release facts/facts.json at ff21de0 (#32). The
changelog sentence extends the last line of the "What a script author sees"
bullet that 0e1ced7 added.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

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Co-authored-by: Claude Opus 5.5 (1M context) <[email protected]>