docs(wiki): refresh agent repository articles

[devswha]

Summary

• Refresh existing wiki articles for patina, oh-my-codex, oh-my-claudecode, oh-my-openagent, gajae-code, and lazycodex with current low-risk facts.
• Add a new sourced article for omnigent-ai/omnigent and link it from the home panel.
• Update the upstream article fixture expectation for the current oh-my-codex release line.

Evidence / sources checked

• gh repo view metadata, latest releases, default branches, homepages, and recent commits for all covered repositories.
• GitHub API README and benchmark sources, including devswha/patina/docs/benchmarks/latest.md.
• GitHub Search API queries for recent AI-agent/developer-tool repositories; selected omnigent-ai/omnigent because it directly matches the wiki's agent-harness coverage and has clear README/source evidence.

Test results

• npm install (local dependency refresh only; tracked node_modules symlink restored)
• npm test -- --run — 65 passed
• npm run typecheck — passed
• npm run build — passed

Merge is left to devswha.