fix: restore missing overview card icons

[userName20260323]

Summary

Restore the missing icons in the Overview documentation card grid. Map Launch WebUI to a globe icon, Architecture to a flowchart icon, and add the missing code and folder icons for Command Reference and Repo Layout. Keep the English and Chinese card order aligned.

Type

• Fix
• Feature
• Docs
• CI / tooling
• Refactor
• Other

Verification

• uv run --group docs mkdocs build --strict -f docs-site/mkdocs.yml: passed

• make check-source-language: passed

• make check-large-files: passed

• uv run python scripts/check_commit_messages.py origin/main..HEAD: passed

• git diff --check: passed

• Mapping check: six English and Chinese cards, six icon mappings, and six well-formed inline SVGs validated

• make lint: partial; Ruff, formatting, import contracts, dependency checks, Python type checks, and UI checks passed, but the bridge build stopped because tsc was not installed in the environment

• Relevant tests pass locally

• Relevant lint / type checks pass locally

• User-facing docs or screenshots are updated when needed

Risk

The change only affects the documentation site's Overview card icons. It does not change runtime behavior, APIs, or user data. The rollback path is to revert this documentation CSS change.

• Security impact considered
• Backward compatibility considered
• Rollback path is clear for risky changes

Related Issues

N/A

[gloryfromca]

No blockers; this can merge as far as I am concerned.

I reviewed the full github/main...HEAD diff and the surrounding overview markup in both locales. The six positional selectors match the six English and Chinese cards, the displaced terminal and folder icons are restored to cards 5 and 6, and the new WebUI and architecture SVGs are well formed and receive distinct mappings.

Coverage included the diff, CSS consumers/callers, introduction history, AGENTS.md and its CLAUDE.md symlink, CONTEXT-MAP.md applicability, backward compatibility, test integrity, and repository architecture constraints. No tests were weakened or removed.

Verification: the strict MkDocs build passed; tests/test_docs_site.py passed (16 tests); source-language, large-file, and git diff --check gates passed; and an independent check confirmed six ordered selectors, six parseable SVGs, and six cards per locale. A browser-level computed-style probe could not run because this environment has no Chrome/Chromium executable; GitHub's docs build is green.