feat(web): add starter suggestions to the empty conversation screen

[elkaix]

Summary

The empty conversation screen showed the mascot, a title, a line of text, and a blank composer. A new user had nothing to click. This adds four starter prompts below the hero text.

• Flat buttons, not cards: no border, background, or shadow. Hover changes the title colour only.
• Two-column grid that collapses to one column on a narrow pane.
• Staggered entry, 200ms each and 45ms apart, disabled under prefers-reduced-motion through the block that already covers the hero.
• A click fills the composer through the existing loadForEdit path and focuses it. It does not send the message.
• The mascot, halo, title and text are unchanged.

Suggestion text lives in a new suggestions i18n namespace, English only. Nothing outside apps/pythinker-web is touched.

Verification

Run from the repository root:

• pnpm run lint — exit 0, no error lines
• pnpm -C apps/pythinker-web run typecheck — exit 0
• pnpm -C apps/pythinker-web exec vitest run — 333 passed, 59 files

Seven new tests in test/empty-suggestions.test.ts cover render-only-when-empty, the click path, the no-submit rule, the flat styling, the reduced-motion rule, and a guard against dark: utilities and new colour literals. Two of them were mutation-checked by hand after the run: removing .empty-suggestion from the reduced-motion block and making the click handler a no-op each turned the suite red.

Summary by CodeRabbit

• New Features

  • Added four starter suggestions to empty conversation screens.
  • Suggestions help explain repositories, find an initial task, run project checks, and review the working tree.
  • Selecting a suggestion loads its prompt into the composer for editing without sending it.
  • Added responsive layout, hover and focus states, animations, and reduced-motion support.

• Tests

  • Added coverage for suggestion visibility, localization, composer behavior, and accessibility interactions.

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📥 Commits

Reviewing files that changed from the base of the PR and between f97b801 and 8d1a677.

📒 Files selected for processing (5)

• .changeset/web-empty-suggestions.md
• apps/pythinker-web/src/components/ConversationPane.vue
• apps/pythinker-web/src/i18n/locales/en/suggestions.ts
• apps/pythinker-web/src/i18n/locales/index.ts
• apps/pythinker-web/test/empty-suggestions.test.ts

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📝 Walkthrough

Walkthrough

The web UI now shows four localized starter suggestions in empty conversations. Selecting a suggestion loads its prompt into the composer without sending it. Responsive styling, reduced-motion support, tests, and a release changeset were added.

Changes

Empty conversation suggestions

Layer / File(s)	Summary
Suggestion content and locale wiring apps/pythinker-web/src/i18n/locales/en/suggestions.ts, apps/pythinker-web/src/i18n/locales/index.ts	Defines four English suggestions with titles, descriptions, and prompts. Registers them in the English locale.
Empty-session suggestion interaction apps/pythinker-web/src/components/ConversationPane.vue	Renders clickable suggestions for empty sessions. Loads the selected localized prompt into the composer without submission. Adds responsive layout, interaction states, entrance animation, and reduced-motion handling.
Interaction and release validation apps/pythinker-web/test/empty-suggestions.test.ts, .changeset/web-empty-suggestions.md	Tests rendering, prompt loading, composer focus, submission prevention, and styling constraints. Documents the minor release change.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Merge Risk: ⚪ Minimal · up to 8d1a6

This localized UI change adds clickable starter suggestions without changing message submission behavior; no actionable merge-blocking risk remains beyond normal checks and review.

Sequence Diagram(s)

sequenceDiagram
  participant User
  participant ConversationPane
  participant EnglishSuggestions
  participant ComposerTextarea
  User->>ConversationPane: Click starter suggestion
  ConversationPane->>EnglishSuggestions: Resolve localized prompt
  EnglishSuggestions-->>ConversationPane: Return prompt text
  ConversationPane->>ComposerTextarea: Populate prompt without submission

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🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description explains the problem, implementation, tests, and verification, but it omits the required Related Issue and Checklist sections.	Add the Related Issue and Checklist sections, and document issue linkage, contribution-guideline review, test coverage, changeset, and documentation status.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title uses the required feat prefix, imperative mood, and is 67 characters long while clearly describing the change.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[pkg-pr-new]

pnpm dlx https://pkg.pr.new/@pymodel/pythinker-code@8d1a677

npx https://pkg.pr.new/@pymodel/pythinker-code@8d1a677

commit: 8d1a677

[elkaix]

Closing: merged locally into main; a new PR will follow.