apigw-lambda-bedrock-js-sam: Update ModelId to Claude Sonnet 4.5

[kakakakakku]

Issue #, if available:
N/A

Description of changes:
Hi😀 Thanks for the useful patterns!

I noticed that Claude v2 can no longer be used. When actually deployed, the following error occurs:

{
    "errorType": "ValidationException",
    "errorMessage": "The provided model identifier is invalid.",
    "name": "ValidationException",
    "$fault": "client",
    "$metadata": {
        "httpStatusCode": 400,
        "requestId": "d7a6a2ac-602f-4a12-9b3e-5beec109b346",
        "attempts": 1,
        "totalRetryDelay": 0
    },
    "stack": [
        "ValidationException: The provided model identifier is invalid.",
        "    at de_ValidationExceptionRes (/opt/nodejs/node_modules/@aws-sdk/client-bedrock-runtime/dist-cjs/protocols/Aws_restJson1.js:299:23)",
        "    at de_InvokeModelCommandError (/opt/nodejs/node_modules/@aws-sdk/client-bedrock-runtime/dist-cjs/protocols/Aws_restJson1.js:101:25)",
        "    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)",
        "    at async /opt/nodejs/node_modules/@smithy/middleware-serde/dist-cjs/deserializerMiddleware.js:7:24",
        "    at async /opt/nodejs/node_modules/@aws-sdk/middleware-signing/dist-cjs/awsAuthMiddleware.js:14:20",
        "    at async /opt/nodejs/node_modules/@smithy/middleware-retry/dist-cjs/retryMiddleware.js:27:46",
        "    at async /opt/nodejs/node_modules/@aws-sdk/middleware-logger/dist-cjs/loggerMiddleware.js:7:26",
        "    at async BufferedInvokeProcessor.handler (file:///var/task/index.mjs:26:15)",
        "    at async BufferedInvokeProcessor.processInvoke (file:///var/runtime/index.mjs:1092:22)",
        "    at async _Runtime.processSingleConcurrent (file:///var/runtime/index.mjs:1178:7)"
    ]
}

Therefore, I updated the model to use Claude Sonnet 4.5 instead.

Check

$ curl -s -d '{"prompt": "Please write 5 lines on Solar Systems"}' -H 'Content-Type: application/json'  https://9zuktk5ty3.execute-api.ap-northeast-1.amazonaws.com/v1/bedrock_test       
{"model":"claude-sonnet-4-5-20250929","id":"msg_bdrk_01S1Rn7gPy3cdRt9aFWf255a","type":"message","role":"assistant","content":[{"type":"text","text":"# Five Facts About Solar Systems\n\n1. **Our Solar System** formed approximately 4.6 billion years ago from a giant rotating cloud of gas and dust called the solar nebula.\n\n2. **The Sun** contains 99.8% of the Solar System's total mass and provides the gravitational force that keeps all planets in orbit.\n\n3. **Eight planets** orbit our Sun in elliptical paths, divided into rocky terrestrial planets (Mercury, Venus, Earth, Mars) and gas/ice giants (Jupiter, Saturn, Uranus, Neptune).\n\n4. **Beyond Neptune** lies the Kuiper Belt, home to dwarf planets like Pluto and countless icy bodies left over from the Solar System's formation.\n\n5. **Scientists estimate** there are billions of other solar systems in our Milky Way galaxy alone, many potentially harboring planets in habitable zones."}],"stop_reason":"end_turn","stop_sequence":null,"usage":{"input_tokens":16,"cache_creation_input_tokens":0,"cache_read_input_tokens":0,"cache_creation":{"ephemeral_5m_input_tokens":0,"ephemeral_1h_input_tokens":0},"output_tokens":192}}

Thank you😀

---

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[kakakakakku]

note: Update for using Messages API.
https://docs.aws.amazon.com/bedrock/latest/userguide/model-parameters-anthropic-claude-messages-request-response.html

[kakakakakku]

note: Update ModelId.

[kakakakakku]

note: Removed JSON.stringify because response escaped like this.

"{\"model\":\"claude-sonnet-4-5-20250929\",\"id\":\"msg_bdrk_016r5f2XBbdEPKDiAD24SJGq\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[{\"type\":\"text\",\"text\":\"# Five Facts About Solar Systems\\n\\n1. **Our Solar System** formed approximately 4.6 billion years ago from a giant rotating cloud of gas and dust called the solar nebula.\\n\\n2. **The Sun** contains 99.8% of all the mass in our Solar System, making it by far the most dominant object gravitationally.\\n\\n3. **Eight planets** orbit our Sun in elliptical paths: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, ranging from rocky inner planets to gaseous outer giants.\\n\\n4. **Beyond Neptune** lies the Kuiper Belt, home to dwarf planets like Pluto and countless icy objects left over from the Solar System's formation.\\n\\n5. **Scientists estimate** there are billions of other solar systems (planetary systems) throughout our Milky Way galaxy alone, many potentially harboring Earth-like worlds.\"}],\"stop_reason\":\"end_turn\",\"stop_sequence\":null,\"usage\":{\"input_tokens\":16,\"cache_creation_input_tokens\":0,\"cache_read_input_tokens\":0,\"output_tokens\":195}}"

[kakakakakku]

typo