feat: add Galaxy-ready CSP inventory CLI

[kgerb]

What changed

• add a headless R CLI and pinned Docker image for CSP stand segmentation
• add repeatable multi-segmentation forest inventory with optional species mappings
• always produce a configurable DTM and optionally add PredInstance_CSP
• preserve original points/dimensions, stage outputs atomically, and record resource metadata
• stream inventory-only fields into disk-backed instance partitions
• add a bounded parallel DTM path: 300 m tiles, 5 m buffer, 10 workers, and automatic 0.1 m minimum-Z streaming above 50 million points
• apply the standardization rlas fix so requested dimensions beyond nine extra-byte records are readable

Why

3Dtrees needs one memory-conscious module that can inventory SAT, ForestMamba, and optional CSP instance segmentations while keeping CSP independently switchable for later SmartTile integration.

Validation

• final image builds and completes the mikro_segmented.laz CLI path without emitting a CSP point cloud
• 38/38 upstream package tests and CLI/parallel-helper tests pass
• supplied-seed CSP on mikro.laz; automatic CSP on upstream beech.las with all 232,083 points preserved
• 5.9M-point GFZ SAT+FM inventory retains exact instance IDs and point counts with 1.33 GiB process peak RSS
• dataset 2056 DTM benchmark: 1,141,911,324 points under a hard 10-CPU/50-GB Docker envelope
• final candidate scan: 56.83 s, 9.51 average CPU cores, 0.78 GiB parent peak RSS, 6.72 GiB conservative worker-peak sum
• 300 m + 5 m CSF/TIN: 81.58 s, 2.93 GiB conservative worker-peak sum, complete aligned 4,758 x 3,490 raster at 0.2 m
• deterministic candidate output across worker counts; unsupported outlier-only edge areas remain NoData

The complete DTM path is validated on dataset 2056. A complete all-segmentation inventory on that dataset remains separate work because its densest 300 m inventory read is still a distinct memory risk.

CI note

PR CI is intentionally disabled for this submodule. Review should use the local validation evidence above.