fix(ci): remove obsolete v1 e2e workflow test (#600)

tests/e2e/test_full_workflow.py asserted against the v1 global
projects/tasks/token_usage tables that PR #596 deliberately dropped
when slimming the control-plane schema (v2 domain data lives in the
per-workspace .codeframe/state.db). The matching test deletion was
missed, breaking the E2E Backend Tests job on main and gating Deploy.

Per tasks/todo.md (issue #599), this file is slated for removal in the
v1-infrastructure cleanup. The modern Golden Path e2e coverage lives in
tests/e2e/cli/.

Co-authored-by: Test User <test@example.com>

Author: frankbria