feat: client panel-router architecture with component-based sidebar

[aaronbrezel]

Summary

• Router navigation stack: Replaces the old two-panel toggle with a Router class that manages a push/pop navigation history, enabling panels to go back to previous panels with their state restored.
• Self-contained components: TagList, SingleTagList, RowRange, and LockableField each own their own DOM subtree, reducing coupling between sidebar logic and HTML structure.
• services.ts as GAS boundary: All google.script.run calls are wrapped as Promises in a single module with a cached header fetch, making panel code fully unit-testable without GAS globals.
• Panels: ToolListPanel (tool list), ConfigureAIRunPanel (AI run config with savedState), RecipesListPanel stub, and DocumentSummarizationPanel stub.
• Cleanup: Deleted old sidebar.ts, sidebar-entry.ts monolith, and all associated tests/fixtures. Updated jest.config.cjs and tsconfig.client.json accordingly.

Architecture

sidebar-entry.ts (init)
└── Router (push/pop stack)
    ├── ToolListPanel          — tool buttons, dispatches via services.ts
    ├── ConfigureAIRunPanel    — column selectors + row range + Run AI button
    ├── RecipesListPanel       — stub
    └── DocumentSummarizationPanel — stub ("Coming soon")

services.ts                   — google.script.run → Promise wrappers + header cache
components/
  tag-list.ts                 — multi-select column tags
  single-tag-list.ts          — single-select + new column option
  row-range.ts                — all/range radio + number inputs
  lockable-field.ts           — locked-by-default input/textarea

Test Coverage

162 tests across 14 suites. Per-file coverage thresholds enforced in jest.config.cjs.

Manual Testing Steps

Prerequisites:

• Deploy to dev with npm run deploy:dev (requires .clasp.dev.json and GAS authorization)
• Open the bound spreadsheet, then Extensions → SSI Tools → Open Sidebar

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1. Sidebar loads — tool list renders

• Expected: Sidebar opens showing three buttons: "Import Drive Links", "Extract Text", "Sample Rows", and "Run AI Inference"
• Expected: No console errors in the browser dev tools (F12 → Extensions → Apps Script → Console not available client-side; check via Ctrl+Shift+J in the sidebar context)

2. Navigate to Configure AI Run

• Click "Run AI Inference"
• Expected: Panel transitions to the AI run configuration view
• Expected: A "← Back" button appears at the top
• Expected: Column selectors appear (User Prompt Columns, Drive File Columns, System Prompt Column, Output Column)

3. Headers load into column selectors

• Expected: After a brief load, column headers from the active sheet populate the tag lists
• Expected: "User Prompt Columns" shows checkboxes for each header
• Expected: "System Prompt Column" and "Output Column" show radio buttons

4. savedState roundtrip — Back and return preserves selections

• Select some columns in the AI run panel (e.g., check a user prompt column)
• Click "← Back" → returns to tool list
• Click "Run AI Inference" again
• Expected: Previously selected columns are not restored (fresh navigation from tool list passes no savedState; savedState is only restored when navigating back from a deeper panel)

5. Back button at root does nothing

• On the tool list, there is no Back button
• If the sidebar is refreshed (GAS reloads the page), it always starts at the tool list

6. Run AI (happy path)

• On a sheet with columns: source_drive, source_text, system_prompt, user_prompt, ai_inference
• Set GEMINI_API_KEY in Apps Script → Project Settings → Script Properties
• Select the appropriate columns in the Configure AI Run panel
• Choose row range and click "Run AI"
• Expected: Button shows "⏳ Running…" and is disabled while running
• Expected: On success, sidebar returns to tool list

7. Run AI (error path)

• Intentionally provide an invalid Gemini API key via Script Properties
• Click "Run AI"
• Expected: Button shows "⏳ Running…" while running, then re-enables on failure
• Expected: An alert() dialog appears with the error message

8. Recipes stub

• Click "Recipes" on the tool list (if visible — may not be wired yet; verify RecipesListPanel is registered)
• Expected: Navigates to a "Recipes" panel with a "Document Summarization" button
• Click "Document Summarization"
• Expected: Panel shows "Coming soon."
• Click Back twice to return to the tool list

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🤖 Generated with Claude Code

[aaronbrezel]

Closing — will re-open as feature branch targeting develop instead.