feat: Add React chat demo gallery

[konard]

Summary

Fixes #1.

This PR converts the starter package into @link-assistant/react-chat-ui and adds a React chat demo gallery for eight researched chat UI options: Stream, Sendbird, CometChat, TalkJS, ChatScope, React Chat Elements, Deep Chat, and assistant-ui.

Implementation

• Adds catalog, theme, language, and design recommendation data in src/chat-demo-catalog.js.
• Adds createChatDemoStore() and a Doublets-compatible Unicode string store with an async doublets-web adapter.
• Adds a Vite React demo in docs/chat-demos with default theme and language switchers for every chat profile.
• Adds browser-commander E2E coverage that opens every demo, verifies theme/language switching and Unicode content, and writes a screenshot.
• Adds a Chat demo pages workflow that builds, tests, uploads the screenshot artifact, deploys to GitHub Pages on main, and runs post-deploy E2E verification.
• Adds the issue Research best React.js chats on the market and make visual demo pages for each of them and docs with screenshots to view all of them #1 case study and captured research data under docs/case-studies/issue-1.

Screenshot

Reproduce

npm install
npm run demo:dev

Open the Vite URL printed by the command and switch through the chat profiles, themes, and languages.

Verification

npm test
bun test --timeout 30000
deno test --allow-read
npm run demo:build
npm run test:e2e
npm run check
bash scripts/check-file-line-limits.sh
npm audit --audit-level=moderate

[konard]

Working session summary

Implemented and pushed the issue #1 solution.

PR: #2
Branch: issue-1-a03cfe4200ef
Commit: 893f73c

What changed:

• Added the React chat demo gallery with 8 researched chat profiles.
• Added theme/language switchers, fake chat data, and Doublets-compatible Unicode storage.
• Added Vite demo app, screenshot asset, browser-commander e2e tests, GitHub Pages workflow, and issue case study data.
• Updated PR 2 title/body and marked it ready for review.

Verification:

• Local: npm test, bun test --timeout 30000, deno test --allow-read, npm run demo:build, npm run test:e2e, npm run check, file line limits, npm audit.
• Browser: desktop/mobile Playwright MCP check passed; screenshot verified.
• CI: all PR checks are passing.

Local demo server is running at: http://127.0.0.1:5176/

Research sources used include: Stream, Sendbird, CometChat, TalkJS, ChatScope, React Chat Elements, Deep Chat, assistant-ui, doublets-web, and browser-commander docs/package pages.

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This summary was automatically extracted from the AI working session output.

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Model: GPT-5.5
• Provider: OpenAI
• Public pricing estimate: $24.073285

📊 Context and tokens usage:

• 651.2K / 1.1M (62%) input tokens, 68.7K / 128K (54%) output tokens

Total: (651.2K + 14.5M cached) input tokens, 68.7K output tokens, $24.073285 cost

🤖 Models used:

• Tool: OpenAI Codex
• Requested: gpt-5.5
• Model: GPT-5.5 (gpt-5.5)

📎 Log file uploaded as Repository (93084KB)

• View complete solution draft log

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Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

✅ Ready to merge

This pull request is now ready to be merged:

• All CI checks have passed
• No merge conflicts
• No pending changes

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