Phase 0: Repository-Initialisierung nach Bauplan v1.2

- Struktur gemäß §8 (Eigentumsgrenzen), PLAN.md als normative Basis
- Pflichtdokumente: STATUS.md, ERRORS.md, TEST_REPORT.md, CHANGELOG.md, ADRs
- ADR-0001 Python 3.13-Pin, ADR-0002 GStreamer 1.28.6-Pin (Windows),
  ADR-0003 IPC TCP+MessagePack v1
- Kernpakete: hms_protocol, hms_domain, hms_parameter, hms_artnet,
  hms_adaptive, hms_capabilities, hms_plugin_sdk
- Renderer-Spike: D3D11-Primärpfad + Dev-GL-Pfad (§36 Nr. 4-5)
- Control Core: FastAPI REST + WebSocket (§36 Nr. 9)
- Beispielplugins: Passthrough + Gaussian Blur (3 Adaptive-Quality-
  Varianten, HLSL/GLSL/GLES)
- Tools: Art-Net-Emulator, Fixture-Generator (Master32/Layer64-CSV),
  Capability-Probe
- JSON-Schemas: IPC, Plugin, Projekt, Cluster
- 121 Unit-/Integrationstests grün, Ruff grün

Gate 0 bleibt offen: Hardwaremessungen nur auf echter Windows-Referenz-
hardware gültig (§29.7, §33).

packages/protocol/hms_protocol/envelope.py

@@ -0,0 +1,37 @@
+"""IPC-Nachrichten-Umschlag (PLAN.md §6.2)."""
+
+from __future__ import annotations
+
+import time
+import uuid
+from enum import StrEnum
+
+from pydantic import BaseModel, Field
+
+PROTOCOL_VERSION = 1
+
+
+class MessageType(StrEnum):
+    COMMAND = "command"
+    EVENT = "event"
+    SNAPSHOT = "snapshot"
+    ACK = "ack"
+    ERROR = "error"
+    TELEMETRY = "telemetry"
+
+
+class Envelope(BaseModel):
+    """Jede IPC-Nachricht besitzt mindestens diese Felder (§6.2)."""
+
+    protocol_version: int = PROTOCOL_VERSION
+    message_id: str = Field(default_factory=lambda: str(uuid.uuid4()))
+    type: MessageType
+    revision: int = 0
+    monotonic_timestamp_ns: int = Field(default_factory=lambda: time.monotonic_ns())
+    payload: dict = Field(default_factory=dict)
+
+    def model_post_init(self, _ctx: object) -> None:
+        if self.protocol_version != PROTOCOL_VERSION:
+            raise ValueError(
+                f"protocol_version {self.protocol_version} != {PROTOCOL_VERSION}"
+            )