chore: add pre-commit hooks, tighten ESLint, activate Sentry DSN, publish CI coverage (Phase 1)

- Install husky v9 + lint-staged: pre-commit runs eslint --fix and prettier on staged files
- Tighten ESLint base config: no-console→error, ban-ts-comment (ts-ignore banned, ts-expect-error with description allowed), reportUnusedDisableDirectives→error
- Migrate web app from deprecated `next lint` to `eslint src/` with flat config and react-hooks plugin
- Convert all 5 @ts-ignore to @ts-expect-error with descriptions, remove stale disable comments
- Add NEXT_PUBLIC_SENTRY_DSN to docker-compose.prod.yml and .env.example
- Add coverage artifact upload step to CI test job
- Pre-existing violations (102 warnings) downgraded to warn in web config for Phase 2 cleanup

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/src/components/ui/ShimmerSkeleton.tsx

@@ -1,6 +1,7 @@
 "use client";
 
-import { Children, cloneElement, isValidElement, ReactNode } from "react";
+import type { ReactNode } from "react";
+import { Children, cloneElement, isValidElement } from "react";
 
 /* ------------------------------------------------------------------ */
 /*  ShimmerSkeleton                                                   */
@@ -44,21 +45,15 @@ export function ShimmerSkeleton({
   const resolvedWidth = width ?? defaults?.width ?? "100%";
   const resolvedHeight = height ?? defaults?.height ?? 40;
   const resolvedRounded = rounded
-    ? roundedMap[rounded] ?? "rounded-md"
-    : defaults?.rounded ?? "rounded-md";
+    ? (roundedMap[rounded] ?? "rounded-md")
+    : (defaults?.rounded ?? "rounded-md");
 
   return (
     <div
       className={`shimmer-skeleton ${resolvedRounded} ${className}`}
       style={{
-        width:
-          typeof resolvedWidth === "number"
-            ? `${resolvedWidth}px`
-            : resolvedWidth,
-        height:
-          typeof resolvedHeight === "number"
-            ? `${resolvedHeight}px`
-            : resolvedHeight,
+        width: typeof resolvedWidth === "number" ? `${resolvedWidth}px` : resolvedWidth,
+        height: typeof resolvedHeight === "number" ? `${resolvedHeight}px` : resolvedHeight,
       }}
     />
   );
@@ -74,11 +69,7 @@ interface ShimmerGroupProps {
   className?: string;
 }
 
-export function ShimmerGroup({
-  children,
-  staggerMs = 50,
-  className,
-}: ShimmerGroupProps) {
+export function ShimmerGroup({ children, staggerMs = 50, className }: ShimmerGroupProps) {
   return (
     <div className={className}>
       {Children.map(children, (child, index) => {