Fix - Align MessageProcessor path normalization with DataContext semantics

[everforge]

Description

This PR aligns MessageProcessor.resolvePath() behavior with existing DataContext path semantics in web_core, improving consistency for relative-path handling.
It adds explicit normalization for "", ".", and "./..." inputs so paths resolve predictably and avoid malformed outputs such as trailing /..

Before: some relative edge cases produced inconsistent results depending on code path.
After: path resolution is consistent across processor/context logic and covered by regression tests.

Fixes: N/A (no tracked issue).

Pre-launch Checklist

• I signed the CLA.
• I read the Contributors Guide.
• I read the Style Guide.
• I have added updates to the CHANGELOG.
• I updated/added relevant documentation.
• My code changes (if any) have tests.

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[gemini-code-assist]

Code Review

This pull request enhances the resolvePath function to correctly handle relative paths like . and ./, as well as empty strings, resolving them against a given context path or the root. Corresponding test cases have been added. The reviewer suggests adding further test cases for resolvePath("./", "/bar") and resolvePath("./") to ensure comprehensive coverage of . and ./ edge cases.

[gemini-code-assist]

The PR description explicitly mentions handling "./..." inputs. While "./foo" is covered, adding a test case for resolvePath("./", "/bar") and resolvePath("./") would ensure complete coverage for the "./" edge case, which currently resolves to the context path (or root) without a trailing slash if the context path doesn't have one, or with a trailing slash if it does.

    assert.strictEqual(processor.resolvePath("."), "/");
    assert.strictEqual(processor.resolvePath("./", "/bar"), "/bar/");
    assert.strictEqual(processor.resolvePath("./"), "/");