Modernize and harden Delphi VCL Inspector — DPI, painting, lifecycle, docs, example

[erdesigns-eu]

Motivation

• Bring the inspector unit up to modern Delphi expectations while preserving its lightweight VCL nature, public API intent, Variant-based values, and VCL Styles support.
• Fix correctness and robustness issues around collection copying, editor lifecycle, focus/keyboard handling, painting, and edge-case geometry.
• Improve DPI/per-monitor behavior so the control preserves the 96‑DPI defaults while scaling correctly under higher DPIs.
• Provide XML IntelliSense documentation for public classes, events and properties and add a minimal example and repo hygiene files to aid adoption.

Description

• Added XML IntelliSense comments to public classes, collections, option classes, events and key properties/methods and preserved existing public API names and semantics.
• Hardened collection and Assign implementations with self-assignment guards, proper deep-copy semantics, and consistent OnChange notifications, and fixed several Assign code paths to call inherited where appropriate.
• Improved editor and selection lifecycle by adding DeactivateEditor, safe IsItemOwned checks, making Enter/Escape behavior explicit for the inline editor, deactivating editors when items are removed or control is disabled, and making property value writes safe using VarSameValue and DisplayText conversion for Null/Empty variants.
• Made painting, layout and editor/button geometry DPI-aware using a Scale helper based on CurrentPPI, guarded bitmap/set-size calls with Max(1, ...) to avoid invalid dimensions, respected disabled text colors, and fixed gutter/splitter hit testing and splitter drag math for scaled coordinates.
• Reduced unnecessary redraws by respecting BeginUpdate/EndUpdate, avoiding updates while deferred, and removing redundant double scroll updates; also improved scroll range clamping with Max(0, ...).
• Added a small code-only example (examples/InspectorDemo) demonstrating categories, collapsed category, editable and edit-button properties, event handlers and a style selector; added a succinct professional README.md and a Delphi .gitignore.

Testing

• Static repository assertions and heuristics were run successfully, including presence of System.Variants usage, XML comment patterns, and scaled geometry tokens (Scale(PropertyOptions.Height)) in Inspector.pas.
• Repository validation checks passed: git -c core.whitespace=cr-at-eol diff --check, git check-ignore for example artifacts, and automated whitespace/line ending checks; these succeeded in this environment.
• Build/runtime validation using the Delphi compiler (dcc32) was not available in the environment and therefore was not executed; manual Delphi compile-and-test is required on Windows to validate VCL Styles rendering, runtime DPI/per-monitor behavior, and editor interactions.
• A commit containing the changes was produced; automated checks performed here succeeded, while platform-specific runtime tests remain manual.

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Codex Task