[annie2013]

Cluster plots can now switch between channel amplitudes and the first four principal components of the combined four-channel waveform, with all six pairings available for picking, brushing and lasso cuts. PCA uses nalgebra to fit a configurable sample, then projects every spike; its basis is reused across cut edits.

• Unify plot controls with neutral joined choices for fixed colours, density and drift, shared by waveform and cluster plots, plus an independent fixed-colour lock in the cluster toolbar. Q switches feature space, L switches brush/lasso, P cycles colours and Shift+P reverses.
• Restore v1's tetrode-wide waveform density scale, including captures. Preserve the position path and speed-histogram canvases across cell, tetrode and cut changes; position or relevant settings changes still invalidate their caches.
• Use regular position sampling for dwell, speed, jump filtering and spike alignment. Add LED-swap detection based on spot sizes and continuity, restore the raw unvisited-bin mask and match v1's directional display rotation. Retain v2's correct LED midpoint, position smoothing and spatial binning.
• Organise Settings by position processing and plot type, with explicit values, units, Off/Auto states and Reset at the top. Use both LEDs when available by default; fix cluster points at 1 px and path spike markers at 3×3 px. Remove cell isolation and spike-count renumbering.
• Put additive file/folder pickers and direct Clear files in the Waveform menu, simplify keyboard help, update the Settings/Headers icons, and clarify clipboard trial/cut selection.
• Fix the stale window-close test locator. Run CI once per PR update, with main-branch builds/deployments and manual runs retained. The 1M browser stress case remains the default; 9M is explicitly opt-in.

Validation

• Production build, ESLint and TypeScript checks pass.
• 39 Rust tests and 25 unit tests pass, including PCA reference cases, Wasm bindings, LED swaps, nominal position timing and spatial masking.
• Full CI run passes: 57 browser tests passed, with 3 optional cases skipped. Coverage includes all four directional orientations, zero speed-histogram redraws across tetrode/cell changes, cache invalidation, clipboard plots, window closing and the independent cluster palette lock.
• Release Wasm is about 655 kB raw / 205 kB gzip.