fix(build): skip redundant AsyncAPI examples fetching when cached

[RohithPariki]

Problem

During the build process (npm run build), scripts/fetch-asyncapi-example.js unconditionally downloaded the examples ZIP file from GitHub, extracted it, and parsed every spec file to generate assets/examples/examples.json.
This network operation ran on every single build, causing:

• Unnecessary network traffic and slower local build times.
• Flaky builds if GitHub or the network was temporarily unreachable or offline even when examples were already present.

Root Cause

scripts/fetch-asyncapi-example.js executed immediately without verifying whether assets/examples/examples.json and the example YAML specs already existed in the local filesystem.

Solution

1. Added shouldSkipFetching() check to verify if assets/examples/examples.json exists, is non-empty, and example YAML files are present in the directory.
2. Added manual override support via --force, -f, or FORCE_FETCH_EXAMPLES=true environment variable so developers and CI can force re-fetching when needed.
3. Added unit tests in test/unit/scripts/fetch-asyncapi-example.test.ts covering all caching conditions, empty files, missing files, and forced overrides.

Testing

• Added and ran unit test test/unit/scripts/fetch-asyncapi-example.test.ts (6 passing tests).
• Verified node scripts/fetch-asyncapi-example.js skips when examples are present.
• Verified node scripts/fetch-asyncapi-example.js --force downloads fresh examples.
• Ran npm run build and npm run lint.

Risk

None. If examples.json does not exist or is invalid, the script falls back to downloading as before.

Checklist

• Tests pass locally
• Lint passes
• Matches existing code conventions
• Regression tests added

Fixes #2015

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Latest commit: fdb9d43

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[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud