UI: Complete missing Arabic translations

[shahar1]

Human Summary

This PR completes missing gaps in the Arabic translation.

Was generative AI tooling used to co-author this PR?

• Yes (GitHub Copilot — Claude Sonnet 4.6)

Generated-by: GitHub Copilot (Claude Sonnet 4.6) following the guidelines

AI Summary

Click here

Complete missing Arabic (`ar`) UI translations so the locale reaches 100% coverage against English.

Changes per file:

• admin.json — jobs columns/filters, pool slots helper text, team column
• assets.json — asset store CRUD labels, events, scheduling, task dependencies
• browse.json — deadlines table columns, status filter options, plural forms
• common.json — token generation UI, bulk clear/update toasters, task/taskGroup labels, states, search, errors, validation messages, partitioned/pending Dag run plurals
• components.json — backfill hints, ISO 8601 duration field, graph zoom, manual-run-denied message; removed 5 stale extra keys
• dag.json — deadline alerts & status section (all plural forms), grid buttons, graph filters panel, version indicator, task stream filter, task store CRUD, logs search, notFound page, storage tab
• dags.json — clearAllMapped action labels
• dashboard.json — deferred-slots-not-counted tooltip and label

Validation: breeze ui check-translation-completeness --language ar reports 1090/1090 keys translated (100%), 0 missing, 0 TODOs, 0 unused.

---

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[jscheffl]

للأسف، اللغة العربية غريبة تماماً عليّ، لكن على الأقل يبدو التصميم جميلاً. موافقة فنية.

[jscheffl]

Keep this non translated?