Add ollama-local module: chat and embeddings against a real local Ollama server

- spring-ai-starter-model-ollama autoconfigures ChatModel/EmbeddingModel from
  spring.ai.ollama.* properties alone; no API key anywhere in this module.
- org.testcontainers:ollama and org.testcontainers:junit-jupiter were both
  renamed in the Testcontainers 2.x line -- to org.testcontainers:testcontainers-ollama
  and org.testcontainers:testcontainers-junit-jupiter respectively -- confirmed by
  reading the real testcontainers-bom-2.0.5.pom that Spring Boot 4.1.1 imports
  (spring-boot-dependencies -> testcontainers.version=2.0.5). The pre-rename
  artifact IDs still exist on Maven Central but are stuck on the 1.x line.
- Unlike every other module in this series, tests drive a real local model
  (qwen2.5:0.5b chat, all-minilm embeddings) via a Testcontainers-managed
  OllamaContainer started from a baked image (scripts/bake-image.sh), not a
  ScriptedChatModel -- the whole point of this post is a real model answering
  a real prompt.
- LocalChatAndEmbeddingTest forces a genuine cold state with Ollama's
  keep_alive: 0 option (set via ChatModel.call(Prompt) -- ChatClient.options()
  does not carry a keepAlive override through to the request in this version)
  and confirms the unload actually happened via /api/ps before measuring a
  reload, rather than trusting whichever call happens to run first.
- On this quiet sandbox host, even a confirmed-cold reload of the 500MB model
  came back in single-digit milliseconds once the underlying image layers were
  cached -- eval (generation) time dominates total latency here, not loading.
  Captured, not asserted as universal: readers get scripts/bake-image.sh to
  get their own numbers.
- Embedding dimension (384, all-minilm) asserted deterministically.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01FtpJvZfg4nvLvtzgJTDWpB

ollama-local/output/03-embedding-dimensions.txt

@@ -0,0 +1,4 @@
+model: all-minilm
+dimensions(): 384
+vector.length: 384
+first 8 values: [-0.02818, -0.00275, -0.02190, -0.03044, 0.02368, -0.08213, -0.10182, -0.05197, ...]