Add PyInstaller spec and Gitea Actions CI for Linux/Windows binaries

- run.py: top-level entry point for PyInstaller (relative imports need it)
- psp-preserve.spec: onedir build bundling DATs, loader, cover bundles, icons
- requirements-build.txt: pinned build deps (PySide6 6.8.3 for Windows ICU fix)
- .gitea/workflows/build.yml: builds linux + windows artifacts on tags/manual
- gitignore build/ dist/

.gitea/workflows/build.yml

@@ -0,0 +1,60 @@
+name: build
+
+on:
+  push:
+    tags: ["v*"]
+  workflow_dispatch:
+
+jobs:
+  linux:
+    name: Linux x86_64
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install build dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements-build.txt
+
+      - name: Build
+        run: pyinstaller --clean --noconfirm psp-preserve.spec
+
+      - name: Package tarball
+        run: tar -czf psp-preserve-linux-x86_64.tar.gz -C dist psp-preserve
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: psp-preserve-linux-x86_64
+          path: psp-preserve-linux-x86_64.tar.gz
+
+  windows:
+    name: Windows x64
+    runs-on: windows
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install build dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements-build.txt
+
+      - name: Build
+        run: pyinstaller --clean --noconfirm psp-preserve.spec
+
+      - name: Package zip
+        shell: pwsh
+        run: Compress-Archive -Path dist\psp-preserve -DestinationPath psp-preserve-windows-x64.zip
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: psp-preserve-windows-x64
+          path: psp-preserve-windows-x64.zip