[KFilippopolitis]

Splits the algorithm panel the way Data Handling was split in #56: a thin app-algorithm-panel shell, attribute-selector sections, and services that the panel provides to its sections. Nothing should look or behave differently.

Structure

• algorithm-panel (shell, 64 lines): same selector, same wiring, and the same API the studio calls (canRun, runDisabledReason, onClickRunExp, setStudioSubstep, studioSubstepChange, onExportResult, onExportResultZip). It provides the services and lays out the card, the readiness bar and the tooltip.
• algorithm-selection/
  • section[app-algorithm-selection]: the card, which hosts role assignment and the details/documentation
  • aside[app-algorithm-catalog]: #algo-search, groups and Runnable/All
  • section[app-algorithm-parameters]
  • div[app-algorithm-config-field]: replaces the untyped ng-template with a typed field input
  • section[app-outlier-report-editor]
  • div[app-algorithm-availability-tooltip]
• experiment-result/
  • div[app-experiment-result]: the readiness bar and error
  • ul[app-algorithm-run-requirements]
• Services (provided by the panel):
  • AlgorithmCatalogService
  • AlgorithmConfigFormService: the form, cross-validation, positive_class and the outlier_report rules
  • AlgorithmRunService: run needs, the run, the error and the PDF/ZIP export
  • AlgorithmStudioSubstepService
• Utils and types: pure helpers are in utils/ with specs, and shared types are in algorithm-panel.models.ts.
• Unchanged: algorithm-result/ (shared).

Cleanup

• Types: 28 lines using any → 0.
• Signals instead of mutable fields:
  • The outlier rules and errors, the built-form signature and the last run algorithm are now signals.
  • Category collapse is a linkedSignal.
  • outlierReportRuleFor is now a pure read. It used to write during render.
• Removed: the unused formKey, yVar, xVar, selectedVariables, isAlgorithmAvailable and the SessionStorage injection.
• Deduplicated: the outlier handlers share one helper.
• CSS: each rule moved to the sheet of the template its element lives in. Shared rules are in styles/*.shared.css. The panel sheet went from 33.2 kB of source (it tripped the budget warning) to 3.3 kB. Every sheet is now under the 20 kB warning, and the warning is gone.

Unchanged

• data-guide anchors (experiment-workspace, algorithm-selection, algorithm-settings)
• #algo-search and all other e2e selectors
• sessionStorage keys
• request payloads

Verification

• npm run verify: passes (no dead code; the only warning is the existing jszip one).
• Vitest: 87 files / 1180 tests pass.
• Playwright: 43/43 pass.
• Visual comparison against master (two runs each, Playwright on separate ports), 6 scenarios:
  • the catalog: search, filters, toggling groups, and an unavailable method selected
  • linear regression with docs, Advanced and cross-validation
  • outlier_report: rules, an invalid fold, the blocked run and the fixed run
  • Cox: select, multi-select and positive_class
  • running, then ZIP and PDF export
  • 900 px and 600 px widths
• Results: all 50 DOM and computed-style dumps, the CTA states, the run request payloads, the session JSON and the ZIP contents are identical. The 24 screenshots are pixel-identical, except one search-field screenshot that also differs between two master runs.

Follow-ups and open questions

1. Form edits can stop persisting (existing bug, kept as is). When a role change leaves the form signature unchanged, the form-build effect returns early. Its cleanup has already unsubscribed the previous form's valueChanges/statusChanges, so later edits are not persisted and formInvalid goes stale.
2. Unreachable tooltip. Nothing calls showTooltip, so the availability tooltip can't be reached from the UI. Remove it or wire it up?
3. outlier_report is excluded from the picker. It is in ALGORITHM_PANEL_EXCLUDED, so its editor only shows for a restored session or edit flow.
4. Share the outlier rule editor with Data Handling once refactor(data-handling): rename the statistics panel to Data Handling and split it into step components and feature services #56 lands (not done here on purpose).