fix(ci): use a dedicated workflow to write comments on PR

[SuperFola]

Description

Use a dedicated workflow to create/update automated PR comments, so that external contributors do not get a 403 when Fuzz testing / Static analysis jobs are running.

Checklist

• I have read the Contributor guide
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have updated the documentation if needed (on https://github.com/ArkScript-lang/website, content/docs/)
• I have added tests that prove my fix/feature is working
• New and existing tests pass locally with my changes
• I confirm that I am the author of this code and release it to the ArkScript project under the MPL-2.0 license. This contribution does not contain code from other sources, including code generated by a Large Language Model ("AI").

[coveralls]

Coverage Report for CI Build 29195736806

Coverage remained the same at 94.38%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	10925
Covered Lines:	10311
Line Coverage:	94.38%
Coverage Strength:	992202.85 hits per line

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💛 - Coveralls