feat(tui): colored status icon

[VascoSch92]

Summary

This PR adds colored status icons (✓ and ✗) to the TUI action view in the Rich Log Visualizer. The checkmark (success) icon is now displayed in green (#6bff6b), while the error icon is displayed in red (#ff6b6b), making it easier for users to quickly identify the outcome of actions.

Changes

• Added SUCCESS_COLOR and ERROR_COLOR constants for consistent color values
• Updated _handle_observation_event() method to use Text.assemble() instead of string concatenation, enabling proper Rich text styling
• Applied color styling to the status icons based on success/error state

Before/After
Before: The status icons (✓/✗) appeared in the default terminal color (white/light gray)

After:
• ✓ checkmark appears in green (#6bff6b)
• ✗ error appears in red (#ff6b6b)

This provides immediate visual feedback on action outcomes without requiring users to parse the icon meaning.

Evidence

The snapshot tests confirm the visual change.
The updated SVG snapshots show the colored icons in action.

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🚀 Try this PR

uvx --python 3.12 git+https://github.com/OpenHands/OpenHands-CLI.git@vasco/check-and-cross

[github-actions]

Coverage Report •

File	Stmts	Miss	Cover	Missing
openhands_cli/tui/widgets
richlog_visualizer.py	351	86	75%	72, 75, 79, 82–85, 87, 175, 182–183, 195, 240, 281, 363, 413–416, 429, 432–434, 437–439, 442, 444, 447, 481–485, 489, 496–499, 503, 515, 556, 561–562, 565–567, 570, 576–579, 581, 588, 602–603, 605, 611, 630–631, 634, 687, 690–691, 695, 705, 708, 725, 727–729, 733, 771–772, 787, 793, 814–815, 819–821, 831–832, 836–838
TOTAL	6639	924	86%

[all-hands-bot]

Taste Rating: 🟢 Good taste - Clean, pragmatic implementation that does exactly what it needs to do.

CODE ANALYSIS:
The implementation is solid. Using Text.assemble() is the correct approach for styled text in Rich/Textual. The color constants are pragmatic, and the logic is straightforward. No special cases, no complexity, no bugs. This is how simple changes should be done.

EVIDENCE NOTE:
The PR description now includes an Evidence section, which is good. For a TUI, the snapshot tests do show the visual output (they're SVG renderings of the exact terminal output). However, for complete evidence, consider adding a screenshot or short GIF of the actual running TUI showing the colored icons in action, not just the test artifacts.

VERDICT: ✅ Ship it - The code is correct and ready to merge. The evidence gap is minor documentation, not a functional issue.

[all-hands-bot]

Taste Rating: 🟢 Good taste - Clean, pragmatic implementation that does exactly what it needs to do.

CODE ANALYSIS:
The implementation is solid. Using Text.assemble() is the correct approach for styled text in Rich/Textual. The color constants are pragmatic, and the logic is straightforward. No special cases, no complexity, no bugs. This is how simple changes should be done.

EVIDENCE NOTE:
The PR description now includes an Evidence section, which is good. For a TUI, the snapshot tests showing the colored icons in SVG format are appropriate proof of the visual changes.

VERDICT: ✅ Worth merging - Solves a real UX problem (quick visual feedback on action status) with clean, maintainable code.

KEY INSIGHT: The change from string concatenation to Rich text assembly is the right technical choice for enabling proper styling without adding complexity.

[VascoSch92]

Hey @malhotra5,

Good catch :-)

I forgot to use .from_markup(...).

Fixed ✅

[malhotra5]

Thanks a bunch!