Learning path: Support SCORM 2004 progress measure

[christianbeeznest]

This PR adds partial SCORM 2004 support for cmi.progress_measure.

Changes

• Adds c_lp_item_view.progress.
• Maps progress in CLpItemView.
• Adds GetValue/SetValue support for cmi.progress_measure.
• Stores the SCO-reported progress as a 0..1 value.
• Does not force progress to 1.0 when completion_status is completed.
• Updates LP progress calculation to use progress_measure for SCORM 2004 items.
• Supports single-SCO and multi-SCO progress calculation.
• Exposes API_1484_11 for SCORM 2004 SCOs.

Tests

• Tested with a minimal SCORM 2004 single-SCO package.
• Verified SetValue("cmi.progress_measure", 0.8) stores progress = 0.8.
• Verified completed status does not overwrite progress to 1.0.
• Verified LP progress uses the stored progress_measure value.