feat: wrap user-facing strings with __() in src2 for i18n

[Copilot]

Extends translation coverage to all user-facing strings in frontend/src2, following the pattern established in #926. Every label, title, message, placeholder, and description visible to users is now routed through the __() translation function.

Scope

• 72 files modified across query/, charts/, dashboard/, workbook/, settings/, users/, teams/, data_source/, data_store/, and helpers/
• Covers .vue templates and .ts logic files (toast messages, confirm dialogs, dropdown options, list column headers, empty states, validation errors)

Pattern

// Before
label: 'Sort Ascending'
title: 'Download Failed'
message: `File "${filename}" exported successfully`

// After
import { __ } from '../translation'

label: __('Sort Ascending')
title: __('Download Failed')
message: __('File "{0}" exported successfully', filename)

Dynamic interpolation uses {0}, {1} etc. as positional placeholders, consistent with the translate() implementation in translation.ts.

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[nextchamp-saqib]

@copilot run pre commit and fix formatting issues in the files changed

Eg. pre-commit run --show-diff-on-failure --color=always --from-ref 3ca6479f0f213753dec696c4a000abe39c08e61f --to-ref 1a8355789cbfbdaf02c90efe318e3ae046934850

[Copilot]

@copilot run pre commit and fix formatting issues in the files changed

Eg. ```pre-commit run --show-diff-on-failure --color=always --from-ref 3ca6479...

Fixed in ccae80b and 7708428. Pre-commit now passes cleanly — trailing whitespace and prettier formatting issues have been resolved across all changed files, and a Vue syntax error in SourceSelectorDialog.vue (title=__(...) → :title="__(...)" ) was also corrected.