Sync upstream v2.8.0-alpha.2 (merge conflicts)

[JOY (JOY)]

Upstream Sync - v2.8.0-alpha.2

Auto-merge with upstream v2.8.0-alpha.2 failed due to conflicts.

To resolve:

1. Check out this branch locally
2. Resolve conflicts
3. Push and merge this PR
4. Then create tag v2.8.0-alpha.2 to trigger Docker build

Upstream release notes

[gemini-code-assist]

Code Review

This pull request implements a major architectural migration for the Blockscout frontend, relocating API services, socket logic, and several key features—including Account, Address Metadata, and Chain Stats—into a domain-driven client/ directory. It also introduces a comprehensive set of rules and skills for AI agents. Technical feedback identifies a logic error in the socket context's provider check, an impure data transformation in the useChainStats hook that mutates state, and a TypeScript type mismatch for a React ref in the ChainStatsSections component.

[gemini-code-assist]

The context is initialized with null (line 20), so useContext will return null when used outside of a provider, not undefined. The check should be updated to correctly identify missing providers.

Suggested change

	if (context === undefined) {
	if (context === null) {

[gemini-code-assist]

The select function in useApiQuery should be a pure function. Here, it performs a shallow clone of the sections array but then mutates the individual section objects (e.g., existingSection.charts = ...). This can lead to unexpected side effects because the original data objects are modified. Consider using a non-mutating approach to merge the sections.

        const sections: Array<ChainStatsSection> = data.sections.map((section) => {
          const extraSection = CROSS_CHAIN_TXS_SECTIONS.find((s) => s.id === section.id);
          if (extraSection) {
            return {
              ...section,
              charts: uniqBy([...section.charts, ...extraSection.charts], (chart) => chart.id),
            };
          }
          return section;
        });

        CROSS_CHAIN_TXS_SECTIONS.forEach((extraSection) => {
          if (!sections.some((s) => s.id === extraSection.id)) {
            sections.push(extraSection);
          }
        });

[gemini-code-assist]

The sectionRef is typed as HTMLUListElement, but it is attached to a <section> element on line 84. This will cause a type mismatch in TypeScript. It should be typed as HTMLElement.

Suggested change

	const sectionRef = React.useRef<HTMLUListElement | null>(null);
	const sectionRef = React.useRef<HTMLElement | null>(null);