WC3 ability refactor: centralize lifecycles and expand save coverage

[sookyboo]

This branch consolidates shared Warcraft III ability behavior while keeping ability-specific decisions in their owning procedures. It introduces shared helpers for spell targeting, channel and thinker identity, timed statuses, summons, corpse selection and reservation, owned effects, and relocation. Abilities retain their own targeting policy, timing, effects, and cleanup behavior.

Persistence coverage now includes live ability state, thinker callbacks, entity generations, owned effects, summons, and corpse reservations. The unit health and unit mana cheats apply to selected controllable units, clamp values to each unit's maximum, and have regression coverage. Documentation reflects the ability architecture and verification guidance.

Rebased onto main, including PR #581. Poison conflict resolution retains main's periodic damage, same-source pulse deadline, and source-incarnation checks while using the shared buff-token, duration, and timed-status helpers.

Network wire format is unchanged. WC3 save format advances from version 64 to 65; prior versions are explicitly rejected.

Validation on rebased head 604c7ff60e37236e8411cb996e6fc475858cc5b1:

• Full make test passed, including both RoC and TFT WC3 engine runs: 46,642 assertions in 2,331 tests per run.
• python3 tools/wc3_ability_class_audit.py --format=coverage completed.
• python3 -m unittest tests/test_check_wc3_ability_registry.py passed all three tests.
• python3 tools/engine_boundary_audit.py --base origin/main passed.
• git diff --check origin/main...HEAD passed; range-diff confirms the rebase only adapts poison handling and documentation context.

Proposed review split, following existing commit dependencies: shared family helpers and ability consumers; delayed identity and persistence with regression tests; documentation and selected-group cheats. Existing commits are preserved through the rebase.