chore: upgrade svelte-sitemap to v3

- bump svelte-sitemap from ^2.8.0 to ^3.1.0
- regenerate lockfile
- update dependency upgrade plan progress

Validation:
- npm run lint
- npm run check
- npm run build

Author: josecelano

docs/dependency-upgrade-plan.md

@@ -11,7 +11,7 @@ remaining major-version bump in a dedicated branch and PR.
 | Patch / minor updates (all except below) | various | latest minor | ✅ Done        | `chore/update-dependencies-2026-04` |
 | `vite`                                   | 8.x     | 8.x          | ✅ Done        | `chore/upgrade-vite-8`              |
 | `@sveltejs/vite-plugin-svelte`           | 7.x     | 7.x          | ✅ Done        | `chore/upgrade-vite-8`              |
-| `svelte-sitemap`                         | 2.x     | 3.x          | ⬜ Not started | —                                   |
+| `svelte-sitemap`                         | 3.x     | 3.x          | ✅ Done        | `chore/upgrade-svelte-sitemap-3`    |
 | `typescript`                             | 5.x     | 6.x          | ⬜ Not started | —                                   |
 | `@types/node`                            | 22.x    | 25.x         | ⬜ Not started | —                                   |
 
@@ -57,9 +57,13 @@ These two must be bumped together: `@sveltejs/vite-plugin-svelte` v7 requires `v
 
 ---
 
-## Phase 2 — svelte-sitemap 2 → 3
+## Phase 2 — svelte-sitemap 2 → 3 ✅
 
-This is a smaller, isolated change.
+This was a smaller, isolated change.
+
+**Branch:** `chore/upgrade-svelte-sitemap-3`
+
+**Result:** completed successfully. `npm run lint`, `npm run check`, and `npm run build` pass, and `build/sitemap.xml` is generated.
 
 **Steps:**
 
@@ -77,6 +81,7 @@ This is a smaller, isolated change.
 
 - CLI argument changes in v3
 - Output format differences in the generated sitemap
+- v3 suggests moving from CLI options to a config file (not required for current setup)
 
 ---
 

package-lock.json

@@ -45,7 +45,7 @@
 		"svelte": "^5.55.4",
 		"svelte-check": "^4.4.6",
 		"svelte-eslint-parser": "^1.6.0",
-		"svelte-sitemap": "^2.8.0",
+		"svelte-sitemap": "^3.1.0",
 		"tailwindcss": "^4.2.2",
 		"tsx": "^4.21.0",
 		"typescript": "^5.9.3",