fix: exclude release scratch dirs from RAT and license skill docs

The apache-rat-plugin runs during the verify phase on every install,
including the six `mvnw ... install` runs in build-release-comet.sh.
RAT walks the root module tree and the exclude list did not cover
several untracked generated/scratch directories that accumulate during
a release (Python virtualenv, docker workdir, extracted tarballs, rat
report files, and the downloaded rat jar). Populated, these make each
RAT pass slow and the build appears to hang. Add excludes for those
paths to the Maven apache-rat-plugin config.

The bash rat check (run-rat.sh) flagged files that the Maven check
already skips. Reconcile the two:

- Add the jni-bridge testdata backtrace/stacktrace fixtures (which
  moved from native/testdata) and .github/workflows/README.md to the
  bash rat exclude list.
- Add the standard ASF license header to the five checked-in
  .claude/skills/*/SKILL.md files so they are properly licensed in the
  release tarball rather than excluded from the license check. The
  header is placed after the YAML frontmatter, which must stay first
  for the skill loader; RAT still detects it.

Author: andygrove

.claude/skills/audit-comet-expression/SKILL.md

@@ -4,6 +4,25 @@ description: Audit an existing Comet expression for correctness and test coverag
 argument-hint: <expression-name>
 ---
 
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
 Audit the Comet implementation of the `$ARGUMENTS` expression for correctness and test coverage.
 
 ## Overview

.claude/skills/bug-triage/SKILL.md

@@ -3,6 +3,25 @@ name: bug-triage
 description: Triage open Comet issues marked `requires-triage` per the project bug triage guide. Applies the recommended priority and area labels, removes `requires-triage`, and files a dated summary issue listing what was done. A human reviews the summary issue and closes it when satisfied.
 ---
 
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
 Run a bug triage pass for the `apache/datafusion-comet` repository.
 
 ## Overview

.claude/skills/implement-comet-expression/SKILL.md

@@ -4,6 +4,25 @@ description: Use when implementing a new Spark expression in DataFusion Comet. W
 argument-hint: <expression-name>
 ---
 
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
 Implement Comet support for the `$ARGUMENTS` Spark expression.
 
 ## Background reading

.claude/skills/review-comet-pr/SKILL.md

@@ -4,6 +4,25 @@ description: Review a DataFusion Comet pull request for Spark compatibility and
 argument-hint: <pr-number>
 ---
 
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
 Review Comet PR #$ARGUMENTS
 
 ## Before You Start

.claude/skills/wire-datafusion-function/SKILL.md

@@ -4,6 +4,25 @@ description: Use when wiring an existing DataFusion or datafusion-spark function
 argument-hint: <expression-name>
 ---
 
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
 Wire Comet support for the `$ARGUMENTS` Spark expression by reusing an existing DataFusion or `datafusion-spark` function. **No native Rust is written here** — if upstream coverage is missing, stop and run `implement-comet-expression`.
 
 ## Wiring patterns

dev/release/rat_exclude_files.txt

@@ -1,12 +1,15 @@
 *.gitignore
 *.dockerignore
 .github/pull_request_template.md
+.github/workflows/README.md
 .gitmodules
 native/Cargo.lock
 native/testdata/backtrace.txt
 native/testdata/stacktrace.txt
 native/core/testdata/backtrace.txt
 native/core/testdata/stacktrace.txt
+native/jni-bridge/testdata/backtrace.txt
+native/jni-bridge/testdata/stacktrace.txt
 dev/copyright/scala-header.txt
 dev/diffs/iceberg/*.diff
 dev/release/requirements.txt

pom.xml

@@ -1167,6 +1167,12 @@ under the License.
             <exclude>docs/source/contributor-guide/*.svg</exclude>
             <exclude>dev/release/rat_exclude_files.txt</exclude>
             <exclude>dev/release/requirements.txt</exclude>
+            <exclude>dev/release/venv/**</exclude>
+            <exclude>dev/release/comet-rm/workdir/**</exclude>
+            <exclude>dev/dist/**</exclude>
+            <exclude>dev/release/rat.txt</exclude>
+            <exclude>dev/release/filtered_rat.txt</exclude>
+            <exclude>dev/release/*.jar</exclude>
             <exclude>native/proto/src/generated/**</exclude>
             <exclude>benchmarks/tpc/queries/**</exclude>
             <exclude>.claude/**</exclude>