fix(web): name conversation menu triggers

[lyzno1]

Summary

• Give each chat-history conversation overflow trigger the established translated common.operation.more accessible name.
• Exercise all pin, unpin, rename, delete, visibility, hover, and propagation flows through the named trigger.
• Replace clickable-div propagation fixtures with a real ancestor event observer.
• Prune the four exact jsx-a11y suppressions that the old test fixtures required.

Behavior contract

• The visually conditional overflow action remains mounted and is announced as More.
• Existing menu visibility, active styling, pin, rename, delete, and deferred callbacks remain unchanged.
• Trigger and popup clicks remain isolated from the conversation-row ancestor.
• This PR does not change the separate conversation item semantics or their remaining suppressions.

Visual regression review

The production change adds only aria-label. No tag, class, style, icon, node order, hover visibility, popup geometry, or interaction state changed, so no visual delta is expected.

Validation

• pnpm exec vp check app/components/base/chat/chat-with-history/sidebar/__tests__/operation.spec.tsx
• node scripts/lint-a11y.mjs app/components/base/chat/chat-with-history/sidebar/operation.tsx
• pnpm exec vp test run app/components/base/chat/chat-with-history/sidebar/__tests__/operation.spec.tsx (15/15)
• 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 (ca3edca).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #40253   +/-   ##
=======================================
  Coverage   86.41%   86.42%           
=======================================
  Files        5107     5107           
  Lines      290731   290750   +19     
  Branches    57917    57923    +6     
=======================================
+ Hits       251245   251268   +23     
+ Misses      34545    34541    -4     
  Partials     4941     4941           

Flag	Coverage Δ
dify-ui	93.49% <ø> (ø)
web	86.11% <100.00%> (+<0.01%)	⬆️

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