Enforce 1-based public trap_index across trap analysis and removal APIs

[charlesmartin14]

Motivation

• Normalize the public-facing trap_index to be 1-based across analysis/artifact outputs and the removal API to avoid off-by-one confusion between internal SVD mode indices and user-visible indices.
• Validate input trap_index values early in remove_traps to prevent passing zero-based indices into the ablation workflow.

Description

• Update analyze_traps to enumerate trap mode indices starting at 1, record artifact trap_index values as 1-based, and adjust plotting and artifact assembly to expect 1-based trap_index values.
• Modify _top_trap_component_row to treat the incoming trap_index as already-public (1-based) and stop adding +1 there.
• Harden remove_traps and _trap_indices_from_traps_df with validation that trap_index values are >= 1, improve handling of per-layer traps selection and propagate selected_trap_indices through cached and non-cached removal paths, and make error messages consistent.
• Adjust apply_remove_traps to validate non-empty, 1-based trap_indices and update the raised error message when invalid indices are detected.
• Update tests to reflect the 1-based public index change: change expected values in test_top_trap_component_row, add test_analyze_traps_public_trap_indices_are_1_based and test_remove_traps_rejects_zero_based_public_trap_index, and simplify a test helper in test_trap_compute_efficiency.py.

Testing

• Ran the modified unit tests including tests/test_analyze_traps.py, tests/test_trap_ablation_workflow.py, tests/test_trap_component_summary.py, and tests/test_trap_compute_efficiency.py which exercise artifact generation, remove workflow, component extraction, and SVD-call behavior respectively, and they all passed.
• Verified that the new validation raises ValueError when zero-based public trap_index values are provided to remove_traps using the added test case which succeeded.
• Confirmed that analyze/remove workflows produce and consume 1-based trap_index values via the added integration-style test which succeeded.

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Codex Task