0.4.0.md

[0.4.0] — 2026-04-18 · Stop 5 pass 1 — client code extracted to src/client/ (branch stop-5/client-split)

Architectural refactor. Client runtime is no longer embedded inside a template literal inside src/html-generator.ts; it now lives as a real TypeScript file that's compiled alongside the server and inlined at generation time. No user-visible behaviour change.

This is pass 1 of the workflow's Stop 5 — a mechanical extraction that moves the whole ~1,100-line embedded script out in one go. Pass 2+ will carve main.ts into smaller panels/, components/, render/, and state/ modules without needing another bulk-extraction turn.

Added

• src/client/main.ts (1,134 lines) — every function, state variable, and bootstrap call that used to live inside the generator's embedded <script>. Written intentionally as a script (no imports, no exports) so tsc emits a plain browser-ready .js runs top-to-bottom.
• src/client/globals.d.ts — ambient declarations for the server-injected globals (DATA, MARKDOWN*, REPORT_NAME, APP_VERSION, GENERATED_AT, DaxHighlight) so the extracted code type-checks without pulling server-only types into the client tree.
• readCompiledClient() helper in html-generator.ts — reads dist/client/main.js at generation time (same three-candidate-path pattern as the DAX vendor files), strips the tsc-inserted export {}; so the inline lands cleanly inside a classic <script>.

Changed

• src/html-generator.ts: 1,740 → 667 lines (−62%). The generator now contains the HTML shell, the inline CSS, the data-injection block (const DATA = …; const MARKDOWN = …; etc.), and a single ${CLIENT_JS} inline for the compiled client bundle. Remaining weight is mostly CSS — a follow-up PR can extract it to src/styles/ and get us to the workflow's ≤ 250-line target.
• No build-pipeline changes. The existing root tsconfig.json already compiles src/client/main.ts → dist/client/main.js because rootDir is ./src. Zero new scripts, zero new config files.

Not included in this PR (deliberate)

• Carving main.ts into 16 smaller modules (panels, components, render, state). That's mechanically independent of the extraction itself and reviews more cleanly as a sequence of smaller PRs. The file has a // @ts-nocheck header so TypeScript doesn't flag the untyped client code — each future carve turns that off for the slice being extracted.
• CSS extraction (would drop html-generator.ts to ~250 lines).
• A dedicated src/client/tsconfig.json — not needed because the root config already handles it.

Test results

49 / 49 green (unchanged; the existing suite already covered what this refactor could break). Build and typecheck clean. Live smoke against test/Health_and_Safety.Report: HTTP 200, dashboard size 752 KB, all 6 key functions (renderMeasures, addCopyButtons, navigateLineage, highlightDaxBlocks, switchTab, bootstrap) present exactly once, no stray export {}; in the output.

Regex regression during development

• tests/render-dax-highlight.test.ts test 21 (addCopyButtons does not call highlightDaxBlocks first) broke because tsc's emitted formatting adds whitespace between ) and { that the inline version didn't have. Relaxed the regex to tolerate whitespace.