chore: upgrade Pulsar client to 4.2.0 and fix V1 topic names in tests

[Croway]

Pulsar 4.2.0 (PIP-457) removed V1 topic name support. Fix test topic URIs that used slashes in the topic name portion, and document the change in the migration guide.

Pulsar 4.2.0 standalone no longer defaults advertisedAddress to localhost, causing the broker to advertise the container hostname. Set PULSAR_PREFIX_advertisedAddress=localhost in the test container.

[github-actions]

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[Croway]

@davsclaus is this section ok here, or should it be in the 4_20 upgrade guide?

[github-actions]

🧪 CI tested the following changed modules:

• components/camel-pulsar
• docs
• parent
• test-infra/camel-test-infra-pulsar

✅ POM dependency changes: targeted tests included

Changed properties: pulsar-version

Modules affected by dependency changes (3)

• :camel-pulsar
• :camel-test-infra-pulsar
• :docs

All tested modules (10 modules)

• Camel :: Docs
• Camel :: JBang :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: Validate
• Camel :: Launcher :: Container
• Camel :: Pulsar
• Camel :: Test Infra :: All test services
• Camel :: Test Infra :: Pulsar
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin

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