frontend: pharmacy inventory, lab add-result & analysis charts

- Pharmacy: the sidebar entry now expands into Pharmacy + a new Inventory page
  (searchable medication stock with derived in-stock/low/out availability,
  backed by /api/inventory). Fix the dispensing-queue "Expiring" badge so it
  only flags courses ending within the next 7 days, not ones already elapsed.
- Lab "Add analysis result": the patient picker no longer lists patients until
  you type and supports arrow-key + Enter selection; the test field offers a
  catalog of common analyses with an Advanced option (custom analysis + ref
  range); submitted results now show immediately in a Recent results feed.
- Analysis: add a Live panel (real-time line chart) and replace the flat trend
  sparklines with bklit-ui area + bar charts (installed from the @bklit shadcn
  registry; chart CSS variables wired into the theme for light and dark).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/components/charts/path-stroke-utils.ts

@@ -0,0 +1,88 @@
+import { type RefObject, useEffect, useState } from "react";
+
+export function findPathLengthAtX(
+  path: SVGPathElement | null,
+  pathLength: number,
+  targetX: number
+): number {
+  if (!path || pathLength === 0) {
+    return 0;
+  }
+  let low = 0;
+  let high = pathLength;
+  const tolerance = 0.5;
+
+  while (high - low > tolerance) {
+    const mid = (low + high) / 2;
+    const point = path.getPointAtLength(mid);
+    if (point.x < targetX) {
+      low = mid;
+    } else {
+      high = mid;
+    }
+  }
+  return (low + high) / 2;
+}
+
+interface PathStrokeMetrics {
+  pathD: string | null;
+  pathLength: number;
+}
+
+const EMPTY_METRICS: PathStrokeMetrics = { pathD: null, pathLength: 0 };
+
+/**
+ * Caller passes the references that drive the rendered path (renderData,
+ * innerWidth, etc.) as `deps`. A stringified summary like
+ * `${renderData.length}:${innerWidth}` is *not* safe here — same-length
+ * in-place mutations of `renderData` keep the summary identical, so the
+ * effect would never re-fire and `pathD`/`pathLength` would stay frozen on
+ * the previous geometry (the area fill repaints from `renderData` directly
+ * and would diverge from the stroke).
+ */
+export function usePathStrokeMetrics(
+  pathRef: RefObject<SVGPathElement | null>,
+  deps: readonly unknown[]
+): PathStrokeMetrics {
+  const [metrics, setMetrics] = useState<PathStrokeMetrics>(EMPTY_METRICS);
+
+  useEffect(() => {
+    const path = pathRef.current;
+    if (!path) {
+      return;
+    }
+    const d = path.getAttribute("d");
+    const len = d ? path.getTotalLength() : 0;
+    setMetrics((prev) =>
+      prev.pathD === d && prev.pathLength === len
+        ? prev
+        : { pathD: d, pathLength: len }
+    );
+  }, deps);
+
+  return metrics;
+}
+
+export function resolveDashTailBounds(
+  dashFromIndex: number | undefined,
+  dataLength: number
+): boolean {
+  return (
+    dashFromIndex != null &&
+    dashFromIndex >= 0 &&
+    dashFromIndex < dataLength - 1
+  );
+}
+
+export function resolveDashStartX(
+  data: Record<string, unknown>[],
+  dashFromIndex: number,
+  xScale: (value: Date | number) => number | undefined,
+  xAccessor: (datum: Record<string, unknown>) => Date | number
+): number {
+  const dashFromPoint = data[dashFromIndex];
+  if (!dashFromPoint) {
+    return 0;
+  }
+  return xScale(xAccessor(dashFromPoint)) ?? 0;
+}