[Java CU SDK] Align cu-sdk-sample-run skill structure with Python; add Sample16 coverage

- Restructure sample-run SKILL: 4 -> 6 numbered steps (Navigate, Build, Configure Env, Choose Sample, Configure Sample-Specific Settings, Run)

- Add Sample16_CreateAnalyzerWithLabels coverage: explicit Manual upload steps, training data file inventory (2 receipts x 3 files), 5-question ASK USER flow, no-training fallback, troubleshooting rows

- Add Sample_Advanced_ToLlmInput entry under Advanced Helpers

- Settings table: add Sample15 cross-resource env vars (SOURCE_RESOURCE_ID, SOURCE_REGION, TARGET_REGION, TARGET_KEY) so it matches what Sample15_GrantCopyAuth.java actually reads

- Sample16 section: clarify SAS prefix trailing slash behavior; note Java parity with Python (Option A only, no auto-upload); Portal navigation hint

- cu-sdk-setup: add ASK USER for Sample16 training data and add SAS URL/PREFIX template add-on

Author: changjian-wang