feat(oauth): import Antigravity Manager account exports

[mertcandrks]

Summary

• Import Antigravity Manager JSON exports for antigravity and agy, normalize nested/flat token formats, refresh stale tokens, verify upstream identity, and reuse existing connection deduplication.
• Add selected-account previews and clear token-bearing preview state on close.
• Enforce a streamed 5 MiB body limit, including requests without Content-Length.
• Recognize camel-case refresh tokens in previews and prevent file replacement while importing.
• Reuse the upstream browser-safe image registry data split from fix(imageRegistry): split data from flag-gated logic to avoid client bundle leak (#10692) #15791, retain the browser-bundle regression test, and avoid duplicating the upstream KeyHealth export fix.

Upstream Conflict Resolution (2026-10-08)

• Merged upstream release/v3.8.52 at 3def9ae3. Resolved the two registry conflicts using the upstream catalog structure and removed the redundant contribution-only data module.
• Fresh post-merge verification: 30 Node tests and 4 Vitest component tests passed, including account import security/persistence, client bundling, and image catalog behavior. Core typecheck, focused ESLint and contribution-only whitespace checks passed.
• Tests used synthetic credentials and isolated temporary databases; no user accounts or live imports were used.
• Metadata cleanup: contribution commit messages and the PR body pass check:ai-attribution; code trees are unchanged. Full npm run lint also passed after integration.
• The broader results below are from the previous head and have not been rerun after this integration; no full-suite or production-build pass is claimed.

Verification

• PASS: 31 focused Node tests covering export normalization, authorization, streamed body limits, verified identity, isolated SQLite persistence, deduplication, existing-account preservation, browser bundling, image catalog behavior and API-key health eviction.
• PASS: 4 Vitest component tests covering selection, malformed JSON, cleanup, camel-case previews and disabled file replacement during import.
• PASS: npm run typecheck:core.
• PASS: focused ESLint on all nine changed source/test files; whitespace and staged privacy checks.
• PASS: real Chrome browser smoke on an isolated data directory: provider page, modal, synthetic file preview/selection, desktop/mobile screenshots, no horizontal overflow, preview cleanup after close. No live account import was submitted.
• No real account exports, credentials, local configuration or user databases are included. All fixtures are synthetic.

Broader Verification / Review Readiness

• PASS: the complete MCP Vitest suite, 494 tests across 54 files.
• Dashboard typecheck: 215 diagnostics on this head versus 216 on upstream a2ed0704; no new file/error-code count buckets. The redundant KeyHealth export diagnostic is removed.
• Full UI suite: 2995 passed, 17 failed, plus two teardown errors. Ten locale-sensitive formatting failures reproduce on the upstream snapshot; seven MCP audit tests timed out in the jsdom suite even though the dedicated MCP suite passes. This suite is not green.
• Full Node suite was stopped after progress stalled in Windows CLI tests: 2625 passing and 18 failing result lines had been emitted, with no final suite summary. Four sampled failures (Windows ESM paths, auto-candidate capability counts and search proxy behavior) reproduce on upstream. Other broad failures are not fully triaged; no full-suite pass is claimed.
• Production build is NOT verified: both webpack attempts exhausted the 8 GiB V8 heap (exit 134). A temporary upstream comparison tree was moved outside the checkout before the second attempt; clean build-scope passes at 10238 files, but the clean-scope attempt still exhausts memory. No production-build pass is claimed.

The focused contribution checks and browser smoke pass; this is submitted for maintainer review, not a claim that every repository gate is green or a request to bypass merge requirements. No merge was performed.

[diegosouzapw]

Hi @mertcandrks — closing this pull request to clear the open queue. The branch feat/antigravity-manager-import is kept, so the commits stay. Comment here if it should be reopened.

[diegosouzapw]

Hi @mertcandrks — reopening this pull request. The close was a mistake, and it is back in the merge queue. The branch feat/antigravity-manager-import was kept.