chore(dev): widen uv range and harden Fedora/AppImage builds (#952)

* chore(deps): allow uv versions below 0.14

* fix(ci): align uv version and generated exports

* fix(dev): check Fedora build headers and AppImage GI bundle

Fail early with distro-specific native dependency hints before dev sync. Verify the AppImage's PyGObject installation and Python path after linuxdeploy, and report isolated GI import failures with actionable path diagnostics. Guard the CI uv pin and cover both preflights with tests.

.github/workflows/unified-pipeline.yml

@@ -135,6 +135,8 @@ jobs:
       - name: Set up uv
         uses: astral-sh/setup-uv@c18668ad3cf93ea998bef934396af7bb5c839dc7 # v10.2.0
         with:
+          # Keep export formatting aligned with the documented generation version.
+          version: "0.13.3"
           enable-cache: true
 
       # --only-group lint installs the linters without the project itself, so
@@ -185,6 +187,7 @@ jobs:
       - name: Set up uv
         uses: astral-sh/setup-uv@c18668ad3cf93ea998bef934396af7bb5c839dc7 # v10.2.0
         with:
+          version: "0.13.3"
           enable-cache: true
           python-version: ${{ matrix.python-version }}
 
@@ -251,6 +254,7 @@ jobs:
       - name: Set up uv
         uses: astral-sh/setup-uv@c18668ad3cf93ea998bef934396af7bb5c839dc7 # v10.2.0
         with:
+          version: "0.13.3"
           # Caches uv's download cache, not .venv/, so the checkout below stays
           # the fresh clone this job exists to exercise.
           enable-cache: true