InspectOptionalContent method

Builds a typed inventory of the document optional-content model and computes effective visibility for one usage and configuration

The method asks PDFium to save the current in-memory document state, then reads the resulting active object graph without depending on private renderer exports

Groups contains object identities, names, Intent values, View/Print/Export states, language and preferred-language metadata, page-element subtype, zoom range, lock state, radio-group membership, and effective visibility

Configurations contains the default configuration followed by alternate configurations, including names, creators, Intent values, /BaseState, /ON, /OFF, /Locked, flattened /Order, /RBGroups, and automatic-state presence

Memberships reports indirect OCMD dictionaries, member groups, policy, original /VE expression text, and the evaluated result with recursion bounded at 32 levels

• Inventory receives all discovered records, the selected configuration index, success state, and diagnostic text
• Usage selects View, Print, Export, or Design semantics for effective visibility
• ConfigurationIndex is zero-based; pass -1 to select the default configuration at index 0

• PDFium exposes no public OCG enumeration or state-switch API, so inspection uses its native save path and mirrors the renderer precedence rules for Usage, configuration state, OCMD policy, and visibility expressions
• The loaded TPdf is not modified and the staging stream follows SaveMemoryLimit spill policy
• A document without /OCProperties returns False with a descriptive ErrorMessage

SaveAsOptionalContentConfigured, RenderPageByIndex, SaveAs