…gle_api (NousResearch#14688)

macOS ships /usr/bin/python3 = 3.9.  When a local-model-backed agent uses
the terminal tool to run `python3 scripts/setup.py --check`, it picks up
that system interpreter rather than the Hermes venv's 3.11+.  On Py3.9
expressions like `Path | None` in a function signature evaluate at
def-time and raise `TypeError: unsupported operand type(s) for |: 'type'
and 'NoneType'` BEFORE the script's try/except ModuleNotFoundError
fallback can run.  Agents interpret the crash as "auth broken" and loop
through setup.

`from __future__ import annotations` (PEP 563) converts every annotation
into a string so the PEP 604 unions never fire at import time.  Py3.10+
users are unaffected.

Files in this PR:
- hermes_constants.py — shared infra, imported transitively by the skill
  scripts; has `Path | None`, `str | None`, `dict | None`, and two
  module-level `bool | None` annotations.
- skills/productivity/google-workspace/scripts/google_api.py — imported
  by setup.py's `--check` path; carries `str | None` and `dict | None`
  on `_gws_binary`/`_run_gws`.

Note: the equivalent fix for `scripts/setup.py` already landed on main
via NousResearch#13038 ("ship google-workspace deps as [google] extra; make setup.py
3.9-parseable").  The test file pins all three files (hermes_constants,
setup, google_api) so the regression guard catches future drift on any
of them.

Tests (tests/skills/test_py39_compat_google_workspace.py):
- AST check that each file starts with `from __future__ import
  annotations` (substring scan would pass false on a docstring mention).
- Verifies each file still contains PEP 604 unions — if a future edit
  strips them all, the pinned list should be reconsidered.
- Smoke test that hermes_constants loads and the previously-crashing
  `get_optional_skills_dir` and `parse_reasoning_effort` return their
  expected values.
- ast.parse(source, feature_version=(3, 9)) on each file — catches any
  Py3.10+-only syntax beyond PEP 604 (e.g. match/case).  Replaces the
  prior `py_compile`-based check, which under the CI interpreter (3.11)
  happily compiled 3.10+-only syntax — Copilot's review on NousResearch#15158
  flagged this and suggested ast.parse with feature_version.

No runtime behavior change on Py3.10+.  On Py3.9 the difference is an
import-time TypeError becoming a clean module load.

Closes NousResearch#14688

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>