fix(ci): set cargo PATH inline in Build step

GITHUB_PATH written by a prior step is not reliably picked up by act
(the local runner). Set PATH directly in the Build step's PowerShell
session so cargo.exe is visible to tauri build.

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

.gitea/workflows/release.yml

@@ -63,27 +63,6 @@ jobs:
           $ver = '${{ needs.prepare.outputs.version }}'
           node -e "const fs=require('fs');const d=JSON.parse(fs.readFileSync('src-tauri/tauri.conf.json','utf8'));d.version='$ver';fs.writeFileSync('src-tauri/tauri.conf.json',JSON.stringify(d,null,2),'utf8');"
 
-      - name: Add Rust to PATH
-        shell: powershell
-        run: |
-          $candidates = @(
-            "$env:USERPROFILE\.cargo\bin",
-            "C:\Users\$env:USERNAME\.cargo\bin"
-          )
-          $added = $false
-          foreach ($dir in $candidates) {
-            if (Test-Path "$dir\cargo.exe") {
-              Add-Content -Path $env:GITHUB_PATH -Value $dir
-              Write-Host "Added $dir to GITHUB_PATH"
-              $added = $true
-              break
-            }
-          }
-          if (-not $added) {
-            Write-Error "cargo.exe not found - install rustup on this runner"
-            exit 1
-          }
-
       - uses: Swatinem/rust-cache@v2
         with:
           workspaces: src-tauri
@@ -109,7 +88,10 @@ jobs:
           CARGO_HTTP_MULTIPLEXING: 'false'
           # Retry transient network errors before failing.
           CARGO_NET_RETRY: '5'
-        run: npm run tauri -- build --bundles nsis
+        run: |
+          $env:PATH = "C:\Users\$env:USERNAME\.cargo\bin;$env:PATH"
+          cargo --version
+          npm run tauri -- build --bundles nsis
 
       - name: Upload to release
         shell: powershell