Summary

Removes four public deprecated aliases that were scheduled for removal in v1.4. The development tree is now 1.6.1dev0 (latest release v1.5.1), so these are two minor versions past their planned removal.

Why now

Each deprecation message advertised removal in v1.14 (and rename in v1.12 / v1.13), which made the removal look far in the future. Those version strings are typos — an extra 1 was inserted after v1.:

• The three model renames actually landed in v1.2.0 — version.py at the rename commit read 1.2.0, and they're documented under the "Current 1.2" section of whats_new.rst.
• The BNCI2014001 rename actually landed in v1.3.0 (Rename deprecated BNCI2014001 to BNCI2014_001 #826).
• The intended removal version was therefore v1.4, not v1.14.

Read correctly, these aliases were due for removal in v1.4. They have now been deprecated for four-plus releases, which is an ample deprecation window, so this PR finishes the job (and removes the misleading version strings in the process).

Migration

# before
from braindecode.models import EEGNetv4
from braindecode.models.attn_sleep import SleepStagerEldele2021
from braindecode.models.tsinception import TSceptionV1
from braindecode.datasets.moabb import BNCI2014001

# after
from braindecode.models import EEGNet, AttnSleep, TSception
from braindecode.datasets import BNCI2014_001

Note: only EEGNetv4 was re-exported at the package level (in braindecode.models.__all__); the other three were only reachable from their submodules.

Changes

• Remove the four alias classes and their now-unused from mne.utils import deprecated imports (kept warn where it is still used in the same module).
• braindecode/models/__init__.py: drop EEGNetv4 from the import and from __all__.
• braindecode/models/util.py: remove the EEGNetv4 special-case in _init_models_dict() — it existed only to hide the alias from the model registry.
• test/unit_tests/models/test_util.py: drop the matching EEGNetv4 exclusion in test_models_dict so the registry/models_dict equality check stays exact.
• test/unit_tests/models/test_config.py: use EEGNet instead of EEGNetv4.
• docs/whats_new.rst: add an entry under "API and behavior changes" for the current release cycle. Historical changelog entries that mention the old names are left untouched as a record.

Testing

• pytest test/unit_tests/models/test_util.py test/unit_tests/models/test_config.py → 136 passed.
• ruff check is clean on all modified files (no unused imports, no undefined names).
• No remaining references to the removed names in .py sources.

Notes

This is a backward-incompatible removal of public API. Happy to retarget it to a specific release if you prefer to batch breaking changes for a particular version.