[ParidelPooya]

Summary

This PR adds best practices for the MicroVM operations. It changes only documentation.

• The extras README gets the section "Best practices for MicroVM operations". It covers deploys and versions, the function timeout, job inputs, job handlers, the HTTP job route, sessions, retry strategies, custom clients and tests, and permissions and monitoring.
• The worker README gets the section "Best practices for job handlers". It covers plain functions and asyncio.run, the result size, and the logger.
• The examples test/README.md gets the subsection "MicroVM Examples and Tests". It covers the SAM deploy, cloud-test inputs as objects, and run_async with wait_for_result.
• Each rule states what happens if it is broken. Each rule appears in one README only, and the sections link to each other.

Why

1. The MicroVM operations guard many edge cases in code.
2. Some of those cases come from a developer's own choices, such as invoking through $LATEST, a custom client, or a route that redirects.
3. A written rule handles such a case with no code to keep in sync across the SDKs.
4. So this PR writes down the rules first. Later PRs can then remove or simplify the safeguards that a rule now covers.

The version rule follows the AWS documentation: an execution started through a version or an alias is pinned to that version, and one started through $LATEST is not. See Invoking durable Lambda functions.

The JS SDK gets the same rules in aws/aws-durable-execution-sdk-js#1076, with JS names.

Testing

• Every claim was checked against the code on main: the 10-second reserve and the 11-second minimum, the 10-second request timeout, the 6 MiB job body, the 4,096-code-point run hook payload, the 256 KB result, the 10-second minimum idle time, the path rules, the 3xx rejection, the 1,000-job duplicate check, and the terminate failure log text.
• The test advice names botocore Stubber only. moto 5.2.4 has no lambda-microvms backend.
• Every relative link and anchor resolves to a heading.
• lintcommit.py passes. The repository has no Markdown check.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[yaythomas]

The new guidance makes the operational requirements easier to find. I checked it against the Python implementation, its tests, and the corresponding JavaScript behavior. The inline suggestions correct minor edge-case wording. None blocks this PR. They can be addressed here or in a follow-up.