feat(core): unify trace collection bindings

[nmrtist]

Summary

• Introduce typed, stable trace collection and item identities for item-addressed series.
• Represent electrophysiology sweeps and pseudo-2D NMR increments through the same trace collection model.
• Unify initial plots, stacked plots, display-mode projection, styling, and persistence around plot-owned series bindings.
• Add strict v1 serialization and reference validation without compatibility parsing or migration logic.

User-facing changes

• Hide legends by default for electrophysiology, pseudo-2D NMR, and true-2D NMR plots while keeping them user-configurable.
• Resolve electrophysiology labels from the varying voltage or current stimulus and pseudo-2D labels from semantic gradient or delay values.
• Preserve editable custom labels, visibility, colors, line widths, scaling, ordering, and stable series identities.
• Expand all trace items when stacking trace collections instead of selecting an arbitrary first item.
• Add Data inspector controls to show all, hide all, remove, reorder, restyle, and choose individual traces.
• Preserve authored stack state when switching pseudo-2D datasets between stack, DOSY, and ILT displays.
• Render DOSY and ILT results as explicit scalar-grid fields through the standard contour pipeline.

Lifecycle and persistence

• Keep sweep analysis selection in transient invocation state.
• Capture selection-dependent tables only through explicit creation actions.
• Prevent unrelated electrophysiology edits from retargeting independently bound channels.
• Validate collection/item references, field compatibility, tagged sources, and owner-local series ID uniqueness consistently on save and load.
• Keep the project schema fixed at version 1.

Documentation

• Update the English and Simplified Chinese electrophysiology and pseudo-2D guides to match the new behavior.

Validation

• cargo pr-check
• Documentation build completed successfully.