Summary

Portal UI overhaul focused on three user-reported defects in the audit and discovery pages, plus the documentation that ships alongside them.

• Audit now has stable column widths (no more jitter when the right pane gets long JSON), method/status pills with color coding, locale-independent 24-hour timestamps, and a sticky detail panel that follows the viewport so clicking the 100th row no longer requires scrolling back to the top.
• Discovery drops the Redoc iframe — it was light-themed inside a dark portal and visibly unreadable — and ships a native OpenAPI 3.1 reference rendered against the portal's design tokens. Full dark/light parity, in-portal search/filter across path/summary/operationId, collapsible operation cards with parameters / request body / responses / synthesized examples, and a tag rail. /docs (Redoc) remains served and is linked from the page header for operators who prefer it.
• Docs + screenshots regenerated: every portal page captured fresh (light + dark), Discovery added to the capture script, operations/portal.md gains a Discovery section, the homepage carousel gets a Discovery slide and an updated Endpoints caption.

Defect → fix mapping

Accessibility / robustness picked up along the way

• aria-expanded on every disclosure (operation cards, response rows).
• Response rows with no body render as a non-interactive <div> so keyboard users don't Tab through dead buttons.
• Tag rail uses aria-pressed for filter state and proper min-w-0 so long tag names don't push the count badge off-screen.
• CodeBlock copy-feedback timer is cleaned up on unmount; the Discovery fetch uses AbortController.
• Loading / missing / error states show contextual subtitles and hide the JSON / YAML / Redoc header links (they 404 together with /openapi.json).
• Method/status pills are color-coded against both light and dark backgrounds.

Files touched

• ui/src/App.tsx — outer grid min-h-full → h-full so main owns the scroll context; sidebar gains overflow-y-auto.
• ui/src/pages/Audit.tsx — fixed-width left column, table-fixed colgroup, 24-hour time, MethodPill/StatusPill, sticky detail panel.
• ui/src/pages/Discovery.tsx — full native OpenAPI viewer replacing the iframe (~760 lines).
• scripts/screenshots/screenshots.mjs — capture Discovery (pre-expanded operation card).
• docs/operations/portal.md — Discovery section + embeds.
• docs/overrides/home.html — carousel adds Discovery; Endpoints caption updated.
• docs/reference/http-api.md — /docs description acknowledges the native portal renderer.
• docs/images/portal/*.png — all regenerated; discovery-{light,dark}.png added.

Verification

Each commit went through make verify (green) plus a live-browser pass before commit:

• Started the rebuilt binary on :8080.
• Authenticated via dev API key against the portal.
• Navigated to each affected page in mcp__claude-in-chrome.
• Ran getBoundingClientRect on every table cell across 20 rows and asserted overflows: [] (first pass found a DELETE pill overflow; widened Method column 72px → 88px; re-measured to zero).
• Scrolled to row 100 and clicked it; asserted the sticky detail panel's top is in-viewport (top: 48px, viewport: 782px).
• Confirmed Dashboard, Endpoints, Discovery still render correctly after the App.tsx layout change.

Test plan

• CI green.
• Hit /portal/audit in a real browser, scroll the list, click rows at the top and bottom — detail panel stays visible.
• Confirm method pills (GET / POST / PUT / PATCH / DELETE) and status pills (2xx / 3xx / 4xx / 5xx) render with readable contrast in both light and dark mode.
• Hit /portal/discovery, expand operation cards, use the search bar, switch tags in the left rail; check that the Redoc link in the header opens /docs in a new tab.
• When /openapi.json is unavailable (e.g. oapiDoc=nil build), Discovery's loading → missing transition does not render dead header links.
• make screenshots against a clean main build reproduces every PNG in this PR.