[release-0.2][backport][api][plan][integrations] Record built-in chat token metrics outside the async call boundary (#712)

[xintongsong]

Backport of #712 to release-0.2. The change keeps token-metric recording on the operator/mailbox (action) thread instead of the durable-execution pool thread, mirroring the Python side of the framework.

Scope on release-0.2

The original PR touched 7 connections; release-0.2 only ships 4 of them. The Bedrock, AzureOpenAI and OpenAIResponses connections are not present on this branch and are intentionally excluded from the backport. Covered connections:

• Ollama
• Anthropic
• AzureAI
• OpenAI (single connection on release-0.2; on main it has since been split into Completions / Responses / AzureOpenAI)

What changed

• BaseChatModelSetup gains public recordTokenMetrics(String, long, long) — the Python-parity record site. The setup's bound metric group is the action metric group, so the emitted metric path and counter names are unchanged.
• BaseChatModelConnection.recordTokenMetrics(...) and the now-dead connection.setMetricGroup(...) forwarding in BaseChatModelSetup are removed.
• Each of the 4 connections' chat() now stashes model_name / promptTokens / completionTokens into the response ChatMessage.extraArgs instead of recording inside chat().
• ChatModelAction records after the durable call returns (before structured-output reassignment, which would drop the keys) via a new static recordChatTokenMetrics(...) helper.
• RunnerContext metric-group getter javadoc now documents that the returned group must only be accessed from the operator/mailbox thread, not inside a durable callable.

Recording is gated identically to Python: non-empty model name and both token counts greater than zero; values are read as Number and converted with longValue() to tolerate Integer/Long across durable recovery.

This also fixes the same latent gap as on main: Python-backed chat models invoked from the Java action previously recorded no token metrics (the path bypasses the Java connection's recording); they are now captured once via the setup.

Tests

• Relocated the base token-metrics test to the setup (BaseChatModelSetupTokenMetricsTest), mirroring the rename on main.
• New ChatModelActionTest covers recordChatTokenMetrics: records when all keys are present and positive; Integer-typed token values still recorded via Number#longValue(); skips when a key is missing or non-numeric; skips when a token is 0 or the model name is empty (Python parity).
• ./tools/build.sh -j and module-level mvn test on api / plan / 4 covered connections all pass locally.

API

Adds public BaseChatModelSetup.recordTokenMetrics(String, long, long) and removes the previously protected BaseChatModelConnection.recordTokenMetrics(...). No change to public configuration, event, or resource APIs. Emitted metric names and paths are unchanged.

Documentation

• doc-needed
• doc-not-needed
• doc-included

[weiqingy]

LGTM