Fix dependency update token mismatch

[alceops]

Fixes #5996.

This makes _apply_env_dep_comparison() robust when the dependency comparison uses a package token such as cuda-version, but the recipe contains a constrained dependency line such as cuda-version >=12,<13.

Changes:

• prefer exact dependency text matches when applying comparison patches;
• fall back to matching the package token before removing/updating;
• skip missing remove/update targets instead of raising a bare ValueError;
• add focused regression coverage for token-match update and missing-remove skip.

Local verification:

• python -m py_compile conda_forge_tick/update_deps.py tests/test_update_deps.py
• git diff --check

I could not run the targeted pytest locally because this runner is missing the test dependency networkx, so I left the PR narrow for CI/review iteration.

[alceops]

Closing this duplicate in favor of #5999 to keep maintainer review focused on one PR. Sorry for the noise.