Add db-migrations-flyway-liquibase: Flyway vs Liquibase migrations, rollbacks and baselines on Spring Boot 4.1

Companion code for the Flyway vs Liquibase article: checksum validation, out-of-order
and repeatable migrations, baselining an existing schema, Flyway Community's undo/diff/deploy
stubs, concurrent-startup locking for both tools, Liquibase changeset identity and rollback
(auto-generated vs explicit), a verified Liquibase 5.0.3 filename-caching defect, the new
OSS license service, the FSL license change, and running both tools against one database.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Q6XdRjtsp4862EM44T7i9a

db-migrations-flyway-liquibase/scripts/run-all.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+# Regenerate every transcript under docs/output/. This module's tests ARE the transcripts —
+# each one asserts the same numbers it writes via the Transcript helper — so a single `mvn test`
+# is the whole regeneration step; there is no separate demo script to drive.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+mvn -q test
+echo "Regenerated: $(ls docs/output | wc -l) files in docs/output/"

db-migrations-flyway-liquibase/scripts/run.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# Runs the demo app with an optional Spring profile, so you can watch each scenario for real
+# instead of only reading about it. See the README's "Try it yourself" table for what each does.
+#
+#   ./scripts/run.sh                 quickstart — Flyway only, clean startup
+#   ./scripts/run.sh both-naive      both tools enabled, no baseline — fails to start on purpose
+#   ./scripts/run.sh both-fixed      both tools enabled, baseline-on-migrate + baseline-version=0
+#
+# Once it's up: curl http://localhost:8080/diag/migrations
+set -euo pipefail
+cd "$(dirname "$0")/.."
+PROFILE="${1:-}"
+if [ -n "$PROFILE" ]; then
+  mvn -q spring-boot:run -Dspring-boot.run.profiles="$PROFILE"
+else
+  mvn -q spring-boot:run
+fi