fix(ci): fetch last 50 commits so changelog has all entries

actions/checkout defaults to fetch-depth: 1 (shallow clone).
generate-changelog runs git log -n 50, so only one entry appeared
in the built app. Fetching 50 commits gives a complete changelog.

Closes #64

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

.forgejo/workflows/ci.yml

@@ -13,6 +13,8 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 50
 
       - name: Enable Nix flakes
         run: |
@@ -30,6 +32,8 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 50
 
       - name: Enable Nix flakes
         run: |
@@ -47,6 +51,8 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 50
 
       - name: Enable Nix flakes
         run: |