[L4XB]

Summary / 概述

parse_env_file (src-tauri/src/gemini_config.rs) skipped export KEY=value lines, because its key check saw export GEMINI_API_KEY. Importing the live config then stored the default Gemini provider without its key, and switching back to it from another provider removed the key from ~/.gemini/.env. Gemini CLI reads the file with dotenv, which accepts the export prefix, and CC Switch's own .env writer (live/patch/dotenv.rs) handles it too.

• parse_env_file strips an export prefix before the key check, like the writer's parse_key.

Related Issue / 关联 Issue

Fixes #8861

Testing

~/.gemini/.env = export GEMINI_API_KEY=AIza-user-key, then import, switch to a second provider and back:

	main	this PR
default provider after import	env: {}	env: {"GEMINI_API_KEY": "AIza-user-key"}
~/.gemini/.env after switching back	empty	export GEMINI_API_KEY=AIza-user-key

• New tests: test_parse_env_file_reads_export_lines (unit) and switching_back_to_imported_gemini_default_keeps_an_export_line_key (integration, in tests/provider_service.rs). On main the integration test fails with an empty .env.
• cargo test: 4248 passed.
• cargo fmt --check passes. cargo clippy --all-targets reports nothing in the changed files (Rust 1.99.1).

Checklist / 检查清单

• cargo clippy passes (if Rust code changed) / 通过 Clippy 检查（如修改了 Rust 代码）
• Rust-only change: no frontend code or user-facing text changed, so pnpm typecheck, pnpm format:check and the i18n files are not affected.

[farion1231]

LGTM, thanks for your contribution!

[farion1231]

Merged, thanks! Nice catch on the read/write asymmetry: the writer already kept export, so teaching the reader the same rule fixes import, routing reads and the switch-back round trip in one place. The byte-for-byte round-trip test is a great guard.