fix(web): lint — eqeqeq, duplicate import, unused var

- ActivityDot.tsx: != → !== (eqeqeq rule)
- PRStatus.tsx: merge duplicate @/lib/types imports into one
- SessionCard.tsx: remove unused activityIcon import

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

packages/web/src/components/ActivityDot.tsx

@@ -28,7 +28,7 @@ interface ActivityDotProps {
 }
 
 export function ActivityDot({ activity, dotOnly = false, size = 6 }: ActivityDotProps) {
-  const c = (activity != null && activityConfig[activity]) || {
+  const c = (activity !== null && activityConfig[activity]) || {
     label: activity ?? "unknown",
     ...fallbackConfig,
   };

packages/web/src/components/PRStatus.tsx

@@ -1,7 +1,6 @@
 "use client";
 
-import type { DashboardPR } from "@/lib/types";
-import { isPRRateLimited } from "@/lib/types";
+import { type DashboardPR, isPRRateLimited } from "@/lib/types";
 import { CIBadge } from "./CIBadge";
 
 function getSizeLabel(additions: number, deletions: number): string {