refactor: remove dead code and dedupe redundant utilities

[GT-610]

Summary

• Remove 42 unused localization keys (verified zero l10n.xxx call sites) across all app_*.arb files and regenerate l10n.
• Remove dead tmux code: TmuxSession.setChoice/buildReconnectCommand/buildAutoCommand/choiceNotifier/lastSessionName, and unused displayName getters on TmuxSessionInfo/TmuxWindowInfo.
• Remove unused res constants: Defaults.primaryColor, Miscs.multiBlankReg, Miscs.jsonEncoder, Urls.cdnBase (and their now-unused dart:ui/dart:convert imports).
• Drop unused ChainComparator.comparing/thenCompareByReversed/reversed() and SudoPassword.hasOverride.
• Dedupe shellSingleQuote: container.dart no longer carries a copy; it forwards to the canonical core/utils/shell_quote.dart implementation (a single-line delegator is required because part files cannot reference imported top-level names inside extension method bodies).
• Replace deprecated EquatableMixin with Equatable mixin in disk.dart; complete the tmux_export.dart barrel export with tmux_window_info.dart.
• Update tests that covered the removed dead code.

Verification

• dart analyze lib reports no issues.
• flutter gen-l10n regenerated.
• flutter test passes (331 tests).

Notes

• Only truly-unused l10n keys were removed; keys that duplicate libL10n names but are still referenced were intentionally left in place.
• Net reduction of ~3173 lines (mostly generated l10n and per-locale arb entries).

Summary by CodeRabbit

• Refactor
  • Simplified comparator and password-override APIs by removing obsolete helpers.
  • Streamlined tmux session handling by removing remembered-session and reconnect/auto-command support; session/window selector labels are now simplified.
  • Centralized shell quoting for more consistent command handling.
  • Removed unused constants and display helpers.
• Localization
  • Pruned outdated translation keys across multiple languages, reducing the set of UI messages shown.
• Tests
  • Updated comparator and tmux session info tests to match the revised APIs and display behavior.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: bbf0cd2f-af3b-4bf8-9425-7db127aa9cd3

📥 Commits

Reviewing files that changed from the base of the PR and between 371a161 and 08baa6e.

📒 Files selected for processing (1)

• lib/data/model/server/disk.dart

🚧 Files skipped from review as they are similar to previous changes (1)

• lib/data/model/server/disk.dart

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📝 Walkthrough

Walkthrough

The pull request removes obsolete comparator, sudo-password, tmux, resource, and localization APIs. It centralizes shell quoting through a shared utility, updates tmux exports, changes Disk equality mixin usage, removes tmux display and reconnect state, and updates related tests. Translation files across supported locales prune obsolete UI, SSH, server, Docker, update, and search keys.

Possibly related PRs

• lollipopkit/flutter_server_box#1183: Both changes update ChainComparator factory and chaining usage.
• lollipopkit/flutter_server_box#1192: Both changes modify tmux session and window models.
• lollipopkit/flutter_server_box#1228: Both changes modify Korean localization keys.

Suggested reviewers: lollipopkit

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: removing dead code and redundant utilities across the project.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cleanup/dead-code

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