feat: resolve KafkaConsumer topics from expressions and config parameters (fixes #693)

[dgafka]

Why is this change proposed?

The KafkaConsumer attribute's topic list was fixed at attribute-scan time, so a multi-tenant deployment needed a full redeploy to pick up a newly added tenant's topic. Ecotone's expression language, already used for tenant resolution elsewhere, was never wired into topic resolution, and there was no single path for resolving cross-framework config values (Symfony container parameters, Laravel config, Tempest config) into it either.

Closes #693 by letting a topics expression pull the list from a referenced service or a config value, evaluated once at first subscribe.

Description of Changes

Resulting flow

Before

graph LR
  A1["topics: 'a', 'b'"] --> B1["scanned once, baked in literally"] --> C1["subscribe('a', 'b')"]

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After

graph LR
  A2["topics: expression string"] --> B2["baked as literal string (unchanged)"] --> C2["first subscribe: evaluate expression"] --> D2["merge + apply topic reference-name mapping"] --> E2["subscribe(resolved topics)"]

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Any topics entry containing ( is now evaluated via the expression language at the first subscribe, instead of being used as a literal topic name. Expression results merge with any literal entries and pass through the existing topic reference-name mapping, same as static topics always have. Tempest's config-variable service is extended to resolve a typed config object's property (previously env-vars only), bringing parameter(...) to parity with the Symfony and Laravel integrations.

Out of scope

• Live re-subscription after startup — topics stay fixed for the process lifetime after the first subscribe.
• Resolving Symfony's native %parameter% placeholder syntax directly — confirmed structurally unreachable for Kafka's isolated container build; parameter(...) inside an expression is the cross-framework path instead.

Example

#[KafkaConsumer(
    endpointId: 'orders',
    topics: "reference('tenantTopics')->getOrderTopics()",
)]

#[KafkaConsumer(
    endpointId: 'orders',
    topics: "parameter('app.multi_tenancy.kafka.orders.topics')",
)]

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