AAS hello-world: pointing OpenUSD at the Asset Administration Shell (PR 105 applied)

[asluk]

Adds a publicly-shareable write-up + slides + one-pager PDF for an applied
demonstration of PR 105 — Separation of Concerns for Identifiers:
a USD prim carries only a stable globalAssetId, and at runtime a consumer
resolves the live Asset Administration Shell (AAS) data and does useful work
with it (a Product Carbon Footprint roll-up with gap-flagging) — without
mirroring that data into the scene (binding-pointer posture).

What's here — extras/sourceIdentifiers/aas-helloworld/

• README.md — the write-up (renders on GitHub): the two-concerns idea, the
  identity-only USD + runtime-injected three-hop resolve (Discovery → Registry →
  Repository, with failover), the binding-pointer posture, what runs today, and
  why gap-flagging is the point.
• aas-usd-helloworld.pptx — slides (10).
• aas-usd-helloworld.pdf — the same content as a one-pager PDF.

Grounding (all public)

• PR 105 (Separation of Concerns for Identifiers)
• AAS DPP ↔ OpenUSD PoC (M. Wagner, SyncTwin) · added mapping document for AAS digital product passport case study OpenUSD-proposals#2
• AAS specifications (IDTA — Metamodel, API, CarbonFootprint IDTA 02023)
• Eclipse BaSyx (open-source AAS stack) + its public Fraunhofer-IESE drivemotor
• Omniverse DSX Blueprint (domain motivation)

Runs end to end for a single component today; the bill-of-materials roll-up is the
next step. Sits alongside COMPARISON.md as the applied counterpart to the
source-identifier comparison work.