build: batch update all dependencies (#9)

## Summary

- Update GitHub Actions: checkout v6.0.2, upload-artifact v6.0.0,
download-artifact v7.0.0
- Update npm deps: svelte 5.53.2 (SSR vulnerability fix),
vite-plugin-svelte 6.2.4, vite 6.4.1, typescript 5.9.3, svelte-check
4.4.1, @tsconfig/svelte 5.0.8, @tanstack/virtual-core 3.13.18
- Add engines.node constraint for vite-plugin-svelte 6.x minimum
- Fix search.test.ts timing for Svelte 5.53.2 reactive system changes

Closes #1, closes #2, closes #3, closes #4, closes #5, closes #6, closes
#7, closes #8

## Test plan

- [ ] CI passes: Go tests, frontend unit tests, E2E tests, lint, type
check
- [ ] `npm audit` shows 0 vulnerabilities
- [ ] Frontend builds cleanly with vite 6.4.1

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: wesm

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 
@@ -37,7 +37,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest]
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 
@@ -71,7 +71,7 @@ jobs:
   coverage:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 
@@ -101,7 +101,7 @@ jobs:
   e2e:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 

.github/workflows/msys2-update-check.yml

@@ -13,7 +13,7 @@ jobs:
   windows-update-check:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 

.github/workflows/release.yml

@@ -33,7 +33,7 @@ jobs:
 
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 
@@ -97,7 +97,7 @@ jobs:
           fi
           rm agentsview${EXT}
 
-      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02  # v4.6.2
+      - uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f  # v6.0.0
         with:
           name: agentsview-${{ matrix.goos }}-${{ matrix.goarch }}
           path: |
@@ -110,11 +110,11 @@ jobs:
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
         with:
           persist-credentials: false
 
-      - uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093  # v4.3.0
+      - uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131  # v7.0.0
         with:
           path: artifacts
           merge-multiple: true