refactor(maps): remove redundant filename-derived tiling metadata

[zoeyrose]

Summary

Remove authored filename-redundant map tiling metadata from atrinik/content@main while preserving intentional topology policy and explicit overrides.

Implementation / behavior

• Audit every coordinate-suffixed authored map against Classic's filename rules and the existing-neighbor check.
• Remove eligible horizontal tile_path_1 through tile_path_8 records and their paired boundary records when no authored seam policy or override is present.
• Apply the same review to vertical tile_path_9 and tile_path_10 only when the filename-derived vertical runtime contract and reciprocal stack checks are live and verified.
• Preserve explicit overrides, policy-bearing seams, unparseable or legacy map names, missing neighbors, and unsupported vertical stacks.
• Add a deterministic validation guard that reports filename-redundant authored tiling metadata before it can be reintroduced.
• Keep generated Classic target artifacts derived from the authored source and preserve map layout and formatting conventions.

Validation

• python3 tools/validate.py
• Focused deterministic tiling-audit and validator tests.
• The applicable Classic target/runtime validation from the same source revision.
• git diff --check

Limitations / follow-up

Vertical cleanup is gated by the explicit filename-derived vertical runtime contract in atrinik/classic#530; no vertical record is removed until that contract and reciprocal checks are live and verified.

Closes #261