update dependency versions and JWT import path

[shivamvishwakarm]

fix: remediate dependency security alerts (Go + Python)

Bumps vulnerable dependencies in go.mod and requirements.txt. Includes a breaking import-path change from golang-jwt/jwt v3 → v4.

Changes

Dependency	From	To	Issue
pgx/v5	v5.7.6	v5.9.2	Memory safety, SQL injection
grpc	v1.78.0	v1.81.1	Auth bypass
jwt	v3.2.2	v4.5.2	Excessive allocation; import path change
otel	v1.38.0	v1.43.0	Excessive allocation
x/image	v0.18.0	v0.38.0	OOM on TIFF decode
go-redis/v9	v9.7.1	v9.7.3	Out-of-order responses
Python protobuf	5.29.5	5.29.6	JSON recursion bypass
Python python-dotenv	1.1.1	1.2.2	Symlink file overwrite