Add six-view LLM-oriented summary mode for aetheris analyze map

[yuechen-li-dev]

Motivation

• Provide a compact, deterministic six-view representation so LLMs can quickly reason about a 3D part silhouette, empty rays, plateaus, and backend provenance without full sample JSON or visual rendering.
• Preserve the existing analytic-first provenance and avoid feature hallucination by surfacing measured first-hit patterns and explicit fallback diagnostics.

Description

• Add a new six-view summary result type and related model shapes: SixViewMapResult, SixViewMapView, SixViewMapSummary, DominantBand, and CompactGrid in Aetheris.CLI/StepAnalysisModels.cs to represent per-view summaries and compact ASCII grids.
• Implement AnalyzeSixViewMapSummary and AnalyzeImportedBodySixViewMapSummary in Aetheris.CLI/StepAnalyzer.cs, which call the existing ray-map backend per orthographic view and build per-view summaries via BuildSixViewSummary, BuildDominantBands, BuildCompactGrid, and BuildMeasuredSummary.
• Wire CLI flags and help: accept --views six with --llm (alias --summary) in Aetheris.CLI/CliRunner.cs, preserve legacy --plane/--direction, --top|--right|... behavior, and document the six-view convention (top xy/-z, bottom xy/+z, right yz/-x, left yz/+x, back xz/+y, front xz/-y).
• Add focused tests and helpers in Aetheris.CLI.Tests/CliBaselineTests.cs for an 8x8 box summary, a torus analytic/no-fallback case, and a RULED-A2 linear-extrusion fallback disclosure case, and add documentation at docs/implementation/analyze-map-a4-six-view-llm-summary.md describing CLI syntax, output fields, compact-grid legend, limitations, and examples.

Testing

• Ran build and unit tests with dotnet restore Aetheris.slnx and dotnet build Aetheris.slnx -f net10.0 --no-restore /m:1, which completed successfully.
• Ran the focused test suite dotnet test Aetheris.CLI.Tests/Aetheris.CLI.Tests.csproj -f net10.0 --filter "AnalyzeMap|SixView|Llm|Compact|Torus|Cylinder|Fallback|Ruled", and the filtered tests passed.
• Exercised the new CLI mode with representative runs: dotnet run --project Aetheris.CLI -- analyze map demos/.../nist_ftc_11_....stp --views six --resolution 16x16 --llm --json and dotnet run --project Aetheris.CLI -- analyze map testdata/step242/generated/ruled-a2/ellipse-linear-extrusion-production.step --views six --resolution 8x8 --llm --json, both returned JSON with expected six-view summaries and fallback diagnostics; dotnet run --project Aetheris.CLI -- analyze volume testdata/.../ellipse-linear-extrusion-production.step --json returned the existing honest unsupported-volume JSON as expected.

Non-scope confirmation: this change preserves the detailed single-view sample JSON and legacy map behavior, does not add analytic hits for linear-extrusion/surface-of-revolution/B-spline families, does not run image rendering or feature reconstruction, and does not change analyze volume policy.

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Codex Task