feat(sim): add land-cover clutter inputs

[Komzpa]

Summary

• add optional land-cover clutter CSV loading and path excess-loss calculation
• add OSM/Overpass-to-clutter CSV exporter as a standalone data-prep tool
• add CLI flags for explicit clutter grids and profile sampling, layered on top of the map/SRTM input slice
• keep terrain on the automatic --terrain-srtm path from feat(sim): add map and terrain inputs #68; this PR only adds clutter CSV as the separate land-cover input
• document clutter input usage and test clutter parsing, cache behavior, and OSM payload validation

Stack

• split from draft rollup feat(sim): add Batumi radio physics for DCR #64
• stacked after feat(sim): add map and terrain inputs #68 / codex/split-input-terrain
• intended review commit for this slice: e8ace19

Validation

• /tmp/meshtasticator-pr68-venv/bin/python -m unittest tests.test_clutter tests.test_osm_clutter tests.test_lora_mesh_cli tests.test_node tests.test_terrain tests.test_map_input
• /home/kom/.local/bin/ruff check loraMesh.py lib/config.py lib/common.py lib/map_input.py lib/node.py lib/packet.py lib/terrain.py lib/clutter.py lib/osm_clutter.py tests/test_clutter.py tests/test_osm_clutter.py tests/test_lora_mesh_cli.py tests/test_node.py tests/test_terrain.py tests/test_map_input.py
• git diff --check
• previously for this slice: compileall; full-suite baseline still has the unrelated test_discrete_sim_ten_nodes messageSeq mismatch from origin/master

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 8d42668099

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".