Release v1.2.0

[roncodes]

Release summary

This is the integration and release branch for @fleetbase/storefront v1.2.0.

• sets the package version to 1.2.0;
• replaces the release-note placeholder with the reviewed v1.2.0 notes;
• receives the complete SDK modernization from PR Modernize Storefront SDK for v1.2 #12;
• uses the repository's release/v<version> merge convention so the version is validated and tagged automatically when this PR merges to main;
• publishes only after the protected release checks and npm environment requirements pass.

Merge order

1. Review and merge PR Modernize Storefront SDK for v1.2 #12 into release/v1.2.0.
2. Confirm the complete CI, package-consumer, framework, security, and mutation matrix is green on this PR.
3. Complete release-candidate application acceptance and configure the documented npm trusted publisher and npm-production environment.
4. Merge this PR into main. The release workflow validates release/v1.2.0, package.json, and RELEASE.md, then creates tag v1.2.0.
5. Verify npm provenance, registry metadata, the GitHub Release, and its attached package/checksum artifacts.

Scope after PR #12 merges

• strict TypeScript implementation with the v1.1.14 public API preserved;
• marketplace/network helpers aligned to the Storefront and Core APIs;
• exact 100% statement, branch, function, and line coverage;
• critical-path mutation testing;
• verified ESM, CommonJS, browser, SSR, and generated TypeScript declarations;
• npm, pnpm, Yarn, Bun, Vite, webpack, Next.js, and Ember consumer validation;
• modern security, dependency, CI, documentation, and protected release automation.

Do not merge this release PR before PR #12 is merged into it and all release gates are complete.