`fixup_for_abi3_version` downgrades version causing wrong link library name when cross-compiling for Android

## Bug Description When cross-compiling an abi3 extension module for Android with `PYO3_CROSS_LIB_DIR` pointing to a Python 3.14 installation (via `build-details.json`), the linker fails with: ``` ld.lld: error: unable to find library -lpython3.7m ``` The target has Python 3.14, but pyo3 generates `-lpython3.7m` instead. See the full CI log: https://github.com/PyO3/maturin-action/actions/runs/24198305015/job/70634639917 ## Root Cause In `from_pyo3_config_file_env()`, after reading the config file (which has `version=3.14`, `abi3=false`), the following happens: 1. `config.abi3 |= is_abi3()` → sets `abi3 = true` (from Cargo feature) 2. `config.fixup_for_abi3_version(get_abi3_version())` → unconditionally sets `self.version = 3.7` (from `abi3-py37` minimum) 3. `apply_default_lib_name_to_config_file()` → computes `lib_name` from the now-downgraded version 3.7 4. `default_lib_name_unix()` for version 3.7 returns `"python3.7m"` (the `m` abiflag workaround for <= 3.7) 5. Since `is_linking_libpython_for_target()` returns `true` for Android, this incorrect library name is emitted as `-lpython3.7m` The fundamental problem is that `fixup_for_abi3_version` downgrades `version` to the abi3 minimum, but `version` is then also used to derive the link library name. The abi3 minimum version is relevant for the Python C API compatibility level, but the **link library** should match the actual target Python installation, not the abi3 minimum. ## Steps to Reproduce 1. Set up cross-compilation for `aarch64-linux-android` 2. Download the Android Python 3.14 standalone build 3. Set `PYO3_CROSS_LIB_DIR` to the Python prefix/lib directory (containing `build-details.json`) 4. Build an abi3 pyo3 crate (e.g., with `abi3-py37` feature) The build will fail with `unable to find library -lpython3.7m`. ## Environment - pyo3 v0.28.2 - Target: `aarch64-linux-android` - Python: 3.14.3 (standalone Android build from python.org) - maturin sets `PYO3_CONFIG_FILE` with `version=3.14`, `abi3=false`, `lib_dir=<PYO3_CROSS_LIB_DIR>`