Refactor Access API gateway to use the unified LocalContextMatcher

[Antherix]

Added a POST /v1/context/query endpoint to the Access gateway that uses
LocalContextMatcher from memact-context for context field matching.
This avoids introducing duplicate matching/scoring logic inside Access
@keepsloading please take a look in the access repo, pls label it under ssoc2026

[Antherix]

@keepsloading assign this to me

[keepsloading]

Resolved. The Access API gateway has been refactored to use the unified LocalContextMatcher from memact-context. Closing this issue.