feat(packaging): nest protocol/ + ocf/ under smartthings_local, add PyPI packaging

Nest the two library packages under a single import namespace so they
can ship as one distribution:

  protocol/ -> smartthings_local/protocol/
  ocf/      -> smartthings_local/ocf/   (git mv, history preserved)

- Rewrite all imports protocol.* -> smartthings_local.protocol.*,
  ocf.* -> smartthings_local.ocf.* across the ocf modules, mqtt_demo/
  (bridge, descriptor, samples), and tests.
- Add pyproject.toml: dist name `smartthings-local`, hatch-vcs versioning
  from v* tags, wheel ships only smartthings_local/.
- Add .github/workflows/publish.yml: build + PyPI Trusted Publishing on
  v* tags (OIDC, no stored token).
- Force-include protocol/ocf_root_ca.pem via [tool.hatch.build] artifacts:
  it is tracked but matches .gitignore's *.pem, so hatchling's VCS file
  selection would drop it — and dtls_session.py loads it at runtime.
- Update mqtt_demo Dockerfile COPY and deploy.sh tar allowlist to the
  single smartthings_local/ package.
- .gitignore: build artifacts (_version.py, dist/, *.egg-info/).

Validated: pytest tests/ (11 passed), python -m build produces sdist +
wheel with the pem bundled, fresh pip install resolves all nested imports
with the pem readable from site-packages.

mqtt_demo/Dockerfile

@@ -8,9 +8,8 @@ RUN pip install --no-cache-dir -r requirements.txt
 
 # Application code — build context is the repo root (see
 # docker-compose.yml's `context: ..`) since mqtt_demo/ depends on the
-# protocol/ and ocf/ library packages that live alongside it.
-COPY protocol/ ./protocol/
-COPY ocf/ ./ocf/
+# smartthings_local library package that lives alongside it.
+COPY smartthings_local/ ./smartthings_local/
 COPY mqtt_demo/ ./mqtt_demo/
 
 # /config holds the ab0b0ac4 client cert + key. Mount from the host so

mqtt_demo/bridge.py

@@ -23,12 +23,12 @@ import time
 
 import cbor2
 
-from protocol.dtls_session import DtlsCoapSession, fmt_code
+from smartthings_local.protocol.dtls_session import DtlsCoapSession, fmt_code
 
-from ocf.keepalive import KeepaliveTask
-from ocf.observe_refresh import ObserveRefreshTask
-from ocf.poll_scheduler import PollScheduler
-from ocf.state_cache import StateCache
+from smartthings_local.ocf.keepalive import KeepaliveTask
+from smartthings_local.ocf.observe_refresh import ObserveRefreshTask
+from smartthings_local.ocf.poll_scheduler import PollScheduler
+from smartthings_local.ocf.state_cache import StateCache
 
 from .descriptor import ApplianceDescriptor, bridge_diagnostic_discovery
 from .config import ApplianceConfig, SharedConfig

mqtt_demo/deploy.sh

@@ -22,7 +22,7 @@ set -e
 
 # This script lives in mqtt_demo/ but the build context is the repo
 # root (mqtt_demo/docker-compose.yml uses `context: ..`, since the
-# image needs the protocol/ and ocf/ library packages alongside
+# image needs the smartthings_local library package alongside
 # mqtt_demo/). Run everything from the repo root so the tar allowlist
 # and remote layout line up with that context.
 cd "$(dirname "$0")/.."
@@ -51,12 +51,11 @@ ssh "${SSH_HOST}" mkdir -p "${REMOTE_DIR}" "${APPDATA_DIR}"
 
 # Source code — explicit allowlist instead of an excludelist. Anything
 # else in the repo (research files, certs, logs, the .git dir) stays
-# local. protocol/ and ocf/ are the library packages mqtt_demo/ imports
-# from; they need to land as REMOTE_DIR's siblings of mqtt_demo/ so the
+# local. smartthings_local/ is the library package mqtt_demo/ imports
+# from; it needs to land as REMOTE_DIR's sibling of mqtt_demo/ so the
 # compose file's `context: ..` resolves the same way it does locally.
 COPYFILE_DISABLE=1 tar cz \
-    protocol/ \
-    ocf/ \
+    smartthings_local/ \
     mqtt_demo/ \
     README.md \
     .gitignore \

mqtt_demo/descriptor.py

@@ -27,7 +27,7 @@ from dataclasses import dataclass, field
 from typing import Callable, Optional, TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from ocf.poll_scheduler import PollTier
+    from smartthings_local.ocf.poll_scheduler import PollTier
 
 
 @dataclass

mqtt_demo/samples/dryer.py

@@ -13,7 +13,7 @@ from ..descriptor import (
     device_block,
     encode,
 )
-from ocf.poll_scheduler import PollTier
+from smartthings_local.ocf.poll_scheduler import PollTier
 
 
 # --- OBSERVE paths -----------------------------------------------------

mqtt_demo/samples/fridge.py

@@ -30,7 +30,7 @@ from ..descriptor import (
     device_block,
     encode,
 )
-from ocf.poll_scheduler import PollTier
+from smartthings_local.ocf.poll_scheduler import PollTier
 
 
 MODEL = 'ARTIK051_REF_17K'

mqtt_demo/samples/oven.py

@@ -31,7 +31,7 @@ from ..descriptor import (
     device_block,
     encode,
 )
-from ocf.poll_scheduler import PollTier
+from smartthings_local.ocf.poll_scheduler import PollTier
 
 
 # ---------------------------------------------------------------------