chore(work): drop unused loop-export complete notification

[stozo04]

Description

Remove dead loop-export "complete" notification surface that has zero callers in production or test code.

What was removed:

• BoomerangRenderNotifications.buildCompleteNotification() function (lines 63–81)
• BoomerangRenderNotificationsRobolectricTest.buildCompleteNotification_usesImmutablePendingIntent() test
• notification_loop_export_complete_title string resource
• notification_loop_export_complete_text string resource

What remains (actively used):

• buildProgressNotification — used by the worker during render
• createForegroundInfo — the foreground service entry point
• Channel setup and FGS type gating — all live

Verified via grep: no remaining references to buildCompleteNotification or the deleted string resources exist in the codebase.

Related Issue

N/A — routine cleanup of unreachable code

Type of Change

• 🔧 Chore: Build configuration changes, dependency updates, or toolchain adjustments

How Has This Been Tested?

• Static Verification: Confirmed zero callers via grep across entire codebase (including tests and all locales)
• Automated Tests: CI will verify build + existing tests pass with the deletions

Checklist

• 🧪 My changes have been verified locally and work as expected.
• 🔍 I have performed a self-review of my own code.
• ✍️ I have commented my code, particularly in hard-to-understand areas. (N/A — deletions only)
• 📖 My changes generate no compile warnings or errors (allWarningsAsErrors is on). (CI will verify)
• 🧹 Pre-PR sweep GREEN on the final commit — Android SDK not available in cloud environment; CI will verify full build
• 🏪 Play-facing docs aligned: N/A — no user-facing changes
• 🧹 The git branch is clean and references to obsolete branches have been pruned.

  

[stozo04]

looks right for tonight's cleanup. dead buildCompleteNotification + unused complete strings + the orphaned robolectric test for it — net -31, progress/FGS path untouched. no behavior change. ready when you are — still draft.