Fix active category chip state on Blogs page filtering

[singhvibhanshu]

Fixes #3007

[greptile-apps]

Greptile Summary

This PR fixes a stale active-chip UI bug on the Blog page where the selected category indicator would not update after browser back/forward navigation or direct URL changes, because selectedCategory was only initialised once from $state.

• A $effect is added that tracks page.url.searchParams and reassigns selectedCategory on every navigation, keeping the chip highlight in sync with the current URL.
• The existing "Clear search" flow (selectedCategory = 'Latest' → handleSearch()) is unaffected because the effect only re-runs when page.url changes, not when selectedCategory is mutated directly.

Confidence Score: 5/5

Safe to merge — the change is a four-line, isolated addition with no side effects on other page functionality.

The fix is minimal and directly targets the root cause: selectedCategory was initialised once at component creation and never updated when the URL changed. Using $effect is the idiomatic Svelte 5 solution. The Clear search path, pagination, and search handlers are all unaffected.

No files require special attention.

Important Files Changed

Filename	Overview
src/routes/blog/[[page]]/+page.svelte	Adds a $effect to keep selectedCategory in sync with the URL's category search param on every navigation, fixing the stale chip highlight bug on back/forward navigation.

_{Reviews (1): Last reviewed commit: "fix(blog): update active category chip U..." | Re-trigger Greptile}