fix(workflows): make ANTHROPIC_API_KEY secret optional

The repository doesn't have this secret, which was causing reusable workflow calls to fail silently.

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

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

Author: MarkusNeusinger

.github/workflows/gen-library-impl.yml

@@ -34,7 +34,7 @@ on:
       CLAUDE_CODE_OAUTH_TOKEN:
         required: true
       ANTHROPIC_API_KEY:
-        required: true
+        required: false
 
 jobs:
   generate:

.github/workflows/gen-new-plot.yml

@@ -201,7 +201,6 @@ jobs:
       deps: "matplotlib>=3.9.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-seaborn:
     needs: [check-conditions, create-sub-issues]
@@ -215,7 +214,6 @@ jobs:
       deps: "seaborn>=0.13.0 matplotlib>=3.8.0,<3.9.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-plotly:
     needs: [check-conditions, create-sub-issues]
@@ -229,7 +227,6 @@ jobs:
       deps: "plotly>=5.18.0 kaleido>=0.2.1 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-bokeh:
     needs: [check-conditions, create-sub-issues]
@@ -243,7 +240,6 @@ jobs:
       deps: "bokeh>=3.4.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-altair:
     needs: [check-conditions, create-sub-issues]
@@ -257,7 +253,6 @@ jobs:
       deps: "altair>=5.2.0 vl-convert-python>=1.3.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-plotnine:
     needs: [check-conditions, create-sub-issues]
@@ -271,7 +266,6 @@ jobs:
       deps: "plotnine>=0.13.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-pygal:
     needs: [check-conditions, create-sub-issues]
@@ -285,7 +279,6 @@ jobs:
       deps: "pygal>=3.0.0 cairosvg>=2.7.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   generate-highcharts:
     needs: [check-conditions, create-sub-issues]
@@ -299,7 +292,6 @@ jobs:
       deps: "highcharts-core>=1.10.0 numpy>=1.26.0"
     secrets:
       CLAUDE_CODE_OAUTH_TOKEN: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
-      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
   # ============================================================================
   # Step 4: Summary after all generations complete