Fix various bugs found during codebase audit

[Flova]

• head_mover: fix sign error in path distance calculation (NaN risk), use pitch acceleration for pitch joint, fix double->int truncation of reduce_last_scanline, replace exact float comparison with epsilon
• odometry: initialize IMU mounting offset transform to identity, as the tf2 default constructor leaves it uninitialized
• world_model: fix inverted rotation in get_uv_from_xy and swapped sin/cos in get_xy_from_uv, remove dead falsiness guards on tuples
• pathfinding: fix angle normalization that produced negative rotation costs in time_to_ball, annotate get_ball_goal as Optional and handle None in go_to_ball
• misc: replace non-existent Duration.to_sec() with nanoseconds / 1e9
• animation: pass float timeout_sec to wait_for_server instead of a Duration object, which raised a TypeError when the server was not immediately available
• team_data: fix docstring of team_rank_to_ball
• costmap: normalize debug costmap to valid OccupancyGrid range [0, 100] instead of overflowing int8, guard against constant costmaps
• ball_filter: remove unused relative estimate lookup that silently skipped the negative observation update on tf errors
• team_communication: compare move_base_goal instead of a function against None, remove illusory hasattr checks on always-present proto3 fields, initialize timestamp state as Optional[TimeMsg]

Checklist

• Run pixi run build
• Write documentation
• Test on your machine
• Test on the robot
• Create issues for future work
• Triage this PR and label it