Study tabs, annotations, and faster analysis comparison

A workspace organized around the task

The right-hand tabs are now Moves, Prediction, Analysis, Position, Explore, Tactical, and Annotations.
Position contains Pawn Structure, Piece Mobility, and King Safety. Engine analysis stays in Analysis.
Explore groups Opening Explorer under Openings and Tablebases under Endgames.
Tactical brings Tactical Map into the sidebar, with gray Insights, Activity, and Patterns subtabs inside a sunken panel.
Annotations replaces the drawing and note toolbar shortcuts and floating windows with Drawings, Notes, and Chess Symbols. Notes are edited inside the panel; common symbols remain in the right-click menu.
Every tab after Moves shows the current position and move. Game Moves fits its contents, and switching between 2D and 3D preserves the live board’s dimensions, including during artwork loading.

Moved Saved Analysis below the Analyze controls.
Added numbered gray buttons in both the normal Analysis view and expanded graph. Click them or press 1–9 to switch runs; the dropdown and active button stay synchronized.
Added per-run engine and settings tooltips. The expanded graph’s engine heading follows the selected historical run rather than the engine configured for future analysis.
Number shortcuts respect text input and unavailable switching states.

Preserved all valid PGN NAG values $0–$255 through saved storage, annotated PGN, and Analysis JSON.
Added descriptions for the original standard set, plus numeric fallbacks for unfamiliar or program-specific codes.
Added a searchable More symbols section under Chess Symbols and an applied-symbol list for individual removal.
Common-symbol edits preserve unrelated advanced annotations. Move tooltips, notes, and reports expose annotations that previously had no displayed symbol.

Cached engine capabilities in memory for the browser session, avoiding a repeated discovery launch when returning to a previously discovered engine.
Added immediate picker feedback and a preparation message for first-time selections. Settings wait until preparation succeeds; discovery failures remain visible.
Refreshing installed engines or changing connections or credentials clears cached capabilities. Opening Engine settings no longer forces a refresh. Actual engine startup and first discovery can still take time.