Fix UOM/quantity mismatches in 2.6 pore-pressure dissipation examples (dictionary check 12)

[xinp-hub]

Summary

Official DIGGS 2.6 pore-pressure dissipation examples fail dictionary check 12 (UOM not valid for the property's quantity class). The 3.0 counterpart already encodes the correct units.

Affected files

• PorePressureDissipationOnly.xml (2.6)
• PorePressureDissipation.xml (2.6)
• CPT_and_PorePressureDissipation.xml (2.6)

Suggested fixes

Property	Current <uom>	Expected (quantity class)
#t50	kPa	s (time)
#coef_consolidation_horiz	cm2/m	cm2/min (area per time)

Reference already-correct 3.0 instance: PorePressureDissipation_Example.xml (s / cm2/min).

Context

Tracked downstream in xinp-hub/pydiggs#220. pydiggs currently surfaces check 12 as a WARNING so official goldens still pass dictionary_check().

[xinp-hub]

Update from pydiggs work on this tracker:

1. t50: please change <uom>kPa</uom> → <uom>s</uom> on the three 2.6 pore-pressure files (3.0 example already uses s).
2. coef_consolidation_horiz: DIGGS 2.6 AllUnits enumerates cm2/m and Kernel.xsd documents it as square centimeter per minute. DiggsUomDictionary uses cm2/min. Keeping cm2/m in 2.6 examples is schema-correct; validators should treat cm2/m ≡ cm2/min. For 3.0, cm2/min remains the preferred spelling.

Downstream: xinp-hub/pydiggs#220