fix(desktop): repair mojibake project labels

[LeonSGP43]

Summary

• repair UTF-8/GBK mojibake in Desktop Projects auto/discovered labels without touching ids or paths
• apply the same display-only repair to projects.discover_repos payloads and auto project tree labels
• add regressions for the garbled 001鍥炴棫 case and for valid Chinese labels staying unchanged

Testing

• uv run --frozen pytest tests/tui_gateway/test_project_tree.py tests/tui_gateway/test_projects_rpc.py
• uv run --frozen ruff check tui_gateway/project_tree.py tui_gateway/server.py tests/tui_gateway/test_project_tree.py tests/tui_gateway/test_projects_rpc.py
• git diff --check

Closes #53367

[tonydwb]

Code Review Summary

Verdict: Approved

Clean fix for mojibake (garbled UTF-8/GBK) project labels in the desktop. The repair_display_label function correctly detects and fixes common UTF-8/GBK encoding issues. Good test coverage with dedicated test cases.

Looks Good

• Well-tested with specific mojibake test cases
• Correct encoding detection and repair logic
• No security concerns
• Small, focused change

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Reviewed by Hermes Agent

[teknium1]

Thanks for tracing the affected Desktop project-label paths. The reported input still flows unchanged on current main through tui_gateway/server.py:11013-11014,11027 and tui_gateway/project_tree.py:621-627, so the fix remains needed.

Problems

• tui_gateway/project_tree.py:70 in d273efabf85e6acaf1df239c62226b803fb00811 accepts a reversible GBK/UTF-8 conversion as evidence of mojibake. Running the exact proposed routine repairs 001鍥炴棫 as intended, but converts the valid Chinese label 一 to Cyrillic һ. The current 项目 regression does not cover this false-positive class.
• The helper is applied to path-derived repository and lane labels at PR lines 133 and 136, and to discovered labels at tui_gateway/server.py:10321-10323, so normal user-visible labels can be changed incorrectly.

Suggested changes

• Restrict repair to labels with a proven malformed-byte provenance instead of applying a generic reversible decode to arbitrary display text.
• Add preservation regressions for 一 and a valid Chinese repository/branch label alongside the reported mojibake case.

Automated hermes-sweeper review.

[teknium1]

Blocking: a GBK→UTF-8 round trip is not proof that value is mojibake. The exact function changes valid Chinese 一 into Cyrillic һ; please constrain this to a proven malformed-label source and add a regression for that false-positive case.