Fusion - the Fusion 360 Bridge

This replaces PR #10 with the completed mechanical foundation integrated onto master 52221e25dcbe11ebccb2dfdaac98c81dec7b8931 (1.11.39). It preserves the newer electronics/routing work and regenerates a 179-verb catalog: all 176 upstream verbs plus the three mechanical entry points. Upstream bridge and add-in version files are unchanged; the maintainer owns release versioning.

The contribution provides 54 typed mechanical operations covering parametric parts, sketch edits and diagnostics, construction geometry and measurements, assemblies with regular/as-built joints, joint origins and motion links, material/physical properties, supplier CAD and BOMs. Document/revision/session targeting and measured recovery protect edits. Completed-operation results are durable, exact duplicates return their recorded result, conflicting payloads refuse, and historical status survives a graceful restart without replaying native work.

McMaster support includes Fusion's interactive picker and verified local STEP/SAT import with provenance. Flat/structured CSV BOMs account for repeated and nested physical instances. Automated retrieval/cache, replacement, pricing/procurement and robust configured/revision-aware BOMs remain gaps. Configuration inspection is read-only: conversion failed native Abort restoration, so writes and full configured archive recovery remain disabled/unqualified.

The dated comparison retains 695 entries across 16 pinned repositories with coverage and gap flags, plus a separate October 5 Autodesk desktop MCP snapshot. See docs/mechanical-comparison/CHECKPOINT-STATUS.md for subsequent feature coverage and docs/integration-2026-10-06.md for integration provenance.

Validation of this exact merged source: 455 Python tests, 62 Rust tests, 38 terminal-history helper tests and 21 busy-status helper tests pass. Eight independent coexistence tests cover the 179-verb union, all 54 typed-operation schemas, stale-board mutation refusal, electronics BOM and schematic planning. Dashboard compilation, portability/import checks and a fresh Windows release build pass. Dashboard has no tests. Source hashes remained unchanged through the gates, and the Windows binary contains the exact regenerated catalog.

Historical native evidence remains attached to its exact earlier source/build. On Fusion 2705.1.11, the assembly checkpoint includes 15 complete groups and 415 passing assertions. On 2705.1.30, dev.8 includes 35 ordinary durable-operation checks, qualified busy-status observation, terminal history across one graceful restart, and stale-session refusal. Original failures and separate qualifications remain intact. These results do not certify the newly merged tree; its native installation/regression acceptance remains pending. The installed dev.8 pin and production package are unchanged.

Rendering and animation are separate future checkpoints. Exploded assembly views are a core animation requirement: ordered disassembly/reassembly steps, individual physical-instance poses, BOM-linked labels and trails while preserving source joints and assembled geometry. docs/EXPLODED-VIEWS.md distinguishes an independent presentation preview from a native editable storyboard, drawing or video. No such capability is claimed here.

Continuous capture and automatic Shotlog uploading are disabled. Routine verification uses structured state, logs and artifact hashes; meaningful visual checks are bounded and reviewed locally. This PR proposes source changes only; no merge or production release has been performed.