fix: keep the latest Chrome password CSV selection

[rudycelekli]

Choosing a second Chrome password CSV before the first file finishes reading can leave the panel showing the second filename while importing the first file's credentials. Clearing the selection can also allow an earlier read to re-enable Import.

Track each selection and ignore results or errors from earlier reads. The regressions cover out-of-order completion, clearing the selection, stale read errors, and a normal single-file import.

Validation: pnpm check --concurrency=1 passed all six tasks (96 files, 880 tests); pnpm build passed with public local placeholders. Local pnpm test:runtime reported two scenarios and all 13 gates passing, then exited 1 at its 180-second Docker cleanup timeout; that local command is not counted as a pass. The focused Vitest tests failed 3/4 before the fix and pass 4/4 afterward. A local Chromium check with the actual React component, original UI primitives, native file input, and native File.text reproduced the wrong imported account before and the selected account afterward. Router and tRPC boundaries and read completion timing were controlled; no saved credentials or external services were used.

The unchanged declared Checks workflow completed successfully on the exact signed source head 88a4866587fe79eb5b10de4ef62a082ff54b4276. Hosted pnpm check passed 96 files / 880 tests and all six check tasks. Hosted pnpm test:runtime completed successfully: both isolated mock-model workflow evals passed all 13 gates, including cleanup. The run used Node 24.21.0 from the declared Node 24 version and pnpm 11.24.0 with the frozen lockfile. The PR merge checkout tree matches the reviewed source head; no workflow, dependency or runtime fixture changes were made.

AI assistance was used for investigation, implementation, tests and review under the submitting account. Signed DCO commit included.