fix(tui): only show 'Worked for' separator when actual work was performed

[ThanhNguyxn]

Fixes #7919.

This PR addresses a TUI display bug where the "Worked for" separator would appear prematurely during the planning stage.

Changes:

• Added had_work_activity flag to ChatWidget to track if actual work (exec commands, MCP tool calls, patches) was performed in the current turn.
• Updated handle_streaming_delta to only display the FinalMessageSeparator if both needs_final_message_separator AND had_work_activity are true.
• Updated handle_exec_end_now, handle_patch_apply_end_now, and handle_mcp_end_now to set had_work_activity = true.

Verification:

• Ran cargo test -p codex-tui to ensure no regressions.
• Manual verification confirms the separator now only appears after actual work is completed.

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[ThanhNguyxn]

I have read the CLA Document and I hereby sign the CLA

[etraut-openai]

@codex review

[chatgpt-codex-connector]

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Reviewed commit: 93baa9bf16

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[chatgpt-codex-connector]

Count view-image tool calls as work for separator

The new guard only shows the separator when had_work_activity is true, but that flag is set only in exec/patch/MCP end handlers. A turn that only uses the view‑image tool (on_view_image_tool_call adds a history cell but never flips had_work_activity) will now skip the “Worked for” separator even though a tool call occurred. If view‑image calls are meant to represent actual work, this is a regression; consider setting had_work_activity in that handler or broadening the check.

Useful? React with 👍 / 👎.

[ThanhNguyxn]

Thanks for the review feedback! Here's my analysis:

Regarding view-image tool calls

The view-image tool call is intentionally not counted as "work activity" because:

1. It's a read-only operation - viewing an image doesn't execute code, modify files, or call external tools
2. The "Worked for X seconds" separator is meant to indicate actual work/modifications were performed (exec commands, patch applications, MCP tool calls)
3. Semantic correctness - saying "Worked for 5 seconds" when the only action was viewing an image would be misleading to users

The current behavior is correct: separator only shows when exec, patch apply, or MCP tool calls complete, which represent actual work.