[Tosd0]

Small fixes found while aligning docs for the stable release.

What changes

Area	Behaviour
Single-user Worker CORS	Content-Encoding is in the default allowed headers, so browsers can send gzip request bodies cross-origin without a custom cors.allowHeaders.
Cloud data cleanup	When an operation stops retrying (8 attempts used up), its error message says retries have stopped.
amsg-client / amsg-instant exports	buildResultPush and isResultPush are re-exported with the other push builders and guards. instant's SessionContext type includes usage.
Example schema.sql	Includes the cloud cleanup work tables, indexes and triggers, so a database built from it alone passes getSchemaVersion.
Comments	Client JSDoc refers to amsg-server 3.0.0; instant's Cloudflare example no longer lists nodejs_compat.

Tests

New tests fail before the fix and pass after:

• Worker preflight allows Content-Encoding.
• Cleanup that exhausts its retries does not promise another retry.
• client and instant re-export every build*Push / is*Push from shared.
• examples/cloudflare-single-user/schema.sql passes getSchemaVersion.

npm run ci: all packages pass.

Merge note

main is still in pre mode. Merging this will open a "Version Packages (next)" PR. Leave that one unmerged; the stable release branch exits pre mode and will pick these changesets up.