ci: skip jobs requiring secrets when running from forks (anthropics#451)

## Summary
- Add `if` conditions to skip e2e test jobs (`test-e2e`,
`test-e2e-docker`, `test-examples`) when PRs come from forks
- Add `if` condition to skip `claude-review` job for fork PRs
- Prevents CI failures for external contributors since fork PRs don't
have access to repo secrets like `ANTHROPIC_API_KEY`

## Test plan
- [ ] Verify that unit tests still run for fork PRs (the `test` job has
no condition)
- [ ] Verify that e2e jobs are skipped for fork PRs
- [ ] Verify that e2e jobs still run for PRs from the main repo
- [ ] Verify that push to main still triggers all jobs

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

Co-authored-by: Claude <[email protected]>

Author: ashwin-ant

.github/workflows/claude-code-review.yml

@@ -12,12 +12,8 @@ on:
 
 jobs:
   claude-review:
-    # Optional: Filter by PR author
-    # if: |
-    # github.event.pull_request.user.login == 'external-contributor' ||
-    # github.event.pull_request.user.login == 'new-developer' ||
-    # github.event.pull_request.author_association == 'FIRST_TIME_CONTRIBUTOR'
-
+    # Skip on forks since they don't have access to secrets
+    if: github.event.pull_request.head.repo.full_name == github.repository
     runs-on: ubuntu-latest
     permissions:
       contents: read

.github/workflows/test.yml

@@ -38,6 +38,8 @@ jobs:
           fail_ci_if_error: false
 
   test-e2e:
+    # Skip on forks since they don't have access to secrets
+    if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
     runs-on: ${{ matrix.os }}
     needs: test # Run after unit tests pass
     strategy:
@@ -82,6 +84,8 @@ jobs:
           python -m pytest e2e-tests/ -v -m e2e
 
   test-e2e-docker:
+    # Skip on forks since they don't have access to secrets
+    if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
     runs-on: ubuntu-latest
     needs: test # Run after unit tests pass
     # Run e2e tests in Docker to catch container-specific issues like #406
@@ -100,6 +104,8 @@ jobs:
             claude-sdk-test python -m pytest e2e-tests/ -v -m e2e
 
   test-examples:
+    # Skip on forks since they don't have access to secrets
+    if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
     runs-on: ubuntu-latest
     needs: test-e2e # Run after e2e tests
     strategy: