fix(web): make tool provider cards buttons

[lyzno1]

Summary

• Render each tool provider card as a native button type="button".
• Map the existing disabled presentation to the native disabled state.
• Preserve the block-card geometry with explicit w-full text-start.
• Cover public button semantics, keyboard activation, and disabled behavior in the owner test.
• Prune the exact two obsolete jsx-a11y suppressions.

Behavior contract

• A tool card is reachable by Tab and opens its read-only details with pointer or Enter activation.
• A disabled card is exposed as disabled, is skipped by browser activation, and does not open details.
• Closing the detail view keeps the existing behavior.

Visual regression review

A temporary Storybook comparison rendered the previous div and the new button under the same production CSS. It was removed before commit.

• Card geometry: 320 x 63 px for both
• Padding: 12 x 16 px for both
• Border: 0.5 px with 12 px radius for both
• Title and description geometry: identical relative coordinates and dimensions
• Text alignment: start for both
• Hover background: rgb(249, 250, 251) for both
• Disabled state: opacity 0.5 and cursor: not-allowed for both

The only intended new visual state is the browser focus indicator during keyboard navigation.

Validation

• pnpm exec vp check app/components/tools/provider/tool-item.tsx app/components/tools/provider/__tests__/tool-item.spec.tsx
• node scripts/lint-a11y.mjs app/components/tools/provider/tool-item.tsx
• pnpm exec vp test run app/components/tools/provider/__tests__/tool-item.spec.tsx (3/3)
• pnpm check (0 errors; 2059 existing warnings)

From Codex

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.42%. Comparing base (e036075) to head (6fa8b4d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #40249   +/-   ##
=======================================
  Coverage   86.41%   86.42%           
=======================================
  Files        5107     5107           
  Lines      290731   290749   +18     
  Branches    57917    57923    +6     
=======================================
+ Hits       251245   251267   +22     
+ Misses      34545    34541    -4     
  Partials     4941     4941           

Flag	Coverage Δ
dify-ui	93.49% <ø> (ø)
web	86.11% <ø> (+<0.01%)	⬆️

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