Update README for 1.9.x specs

[ChiragAgg5k]

What changed

• Added 1.9.x to the README available versions table.
• Updated README usage examples from 1.8.x to 1.9.x.

Testing

• npm ci --no-audit --no-fund
• npm run validate:refs -- specs

[greptile-apps]

Greptile Summary

This PR updates the README to document the 1.9.x spec release: it adds a new row to the available-versions table and bumps the usage examples (curl download URL, openapi-generator invocation, and CLI generation command) from 1.8.x to 1.9.x. All referenced paths (specs/1.9.x, examples/1.9.x, and open-api3-1.9.x-server.json) are confirmed present in the repository.

Confidence Score: 5/5

Safe to merge — purely a documentation update with all referenced assets verified.

The change is limited to README documentation. All linked directories and files exist in the repo, the table ordering is correct (newest first), and no logic or code is affected.

No files require special attention.

Important Files Changed

Filename	Overview
README.md	Adds 1.9.x row to the versions table and updates usage examples (curl download path, openapi-generator command, and CLI generation command) from 1.8.x to 1.9.x; all referenced files and directories exist in the repository.

_{Reviews (1): Last reviewed commit: "Update README for 1.9.x specs" | Re-trigger Greptile}