Set up DOTS + Netcode for Entities foundation

One-time stack setup per Docs/dots-setup-task.md (Unity 6.4.7 / 6000.4.7f1).
Packages: entities 6.4.0, entities.graphics 6.4.0, netcode 1.13.2, physics 1.4.6.

- Assets/_Project asmdef split: ProjectM.Simulation/Client/Server/Authoring (root ns ProjectM)
- GameBootstrap : ClientServerBootstrap; verified separate client + server worlds in Play Mode
- Gameplay subscene wired into SampleScene as a baking target
- Heartbeat component + Burst ISystem; EditMode smoke test green (1/1)
- In-repo Obsidian vault (Docs/Vault) incl. DR-001 (plain-Entities test over internal NetCodeTestWorld)
- Portable .mcp.json (basic-memory + serena via ${CLAUDE_PROJECT_DIR}); CLAUDE.md conventions
- .gitignore for DOTS baking cache + machine-local config

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Docs/Vault/_Meta/Documentation_Protocol.md

@@ -0,0 +1,37 @@
+---
+tags:
+- meta
+- protocol
+updated: 2026-05-29
+permalink: gamevault/meta/documentation-protocol
+---
+
+# Documentation Protocol
+
+How knowledge is read and written for Project M. Four layers, each with a distinct job; the **in-repo vault is the single source of human-facing, cross-machine truth**.
+
+## Layers
+
+| Layer | Holds | Crosses machines? |
+|---|---|---|
+| **This vault** (`Docs/Vault/`) | Design docs, decision records, session logs, roadmap | **Yes** (git) |
+| **basic-memory** MCP | Semantic + wikilink recall over these same vault files | Yes (indexes the vault) |
+| **serena** MCP | C# symbol navigation of `Assets/_Project/` | N/A (from code) |
+| **Native Claude memory** | Machine-local facts / preferences (`memory/`, `MEMORY.md`) | **No** |
+
+**Cross-machine rule:** durable truth → vault or repo `CLAUDE.md` (both committed). Native memory is local-only, never the sole home of a decision or design fact.
+
+## Which tool when
+
+- Where is X defined / who calls it → **serena** (fallback `Grep` / `Glob`).
+- What did we decide / how does system Z work → **basic-memory** recall → read the note here.
+- Literal string / asset GUID → **Grep / Glob**.
+- Current DOTS / Netcode API → **context7** (never memory).
+- Conventions / preferences → repo `CLAUDE.md` + native memory.
+
+## Session bookends
+
+- **Start (read-only):** `CLAUDE.md` → [[Home]] + latest session log → open decision records + [[Backlog]] → basic-memory recall on the goal's nouns.
+- **End:** write a session log (`07_Sessions/<year>/`) → firm decisions to DR records → edit touched design docs in place (wikilink, don't duplicate) → durable knowledge to basic-memory, machine-local facts to native `MEMORY.md`.
+
+Driven by the `/dots-dev` skill; this scaffold was created by the one-time setup task.

Docs/Vault/_Meta/Tags.md

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+---
+tags:
+- meta
+- taxonomy
+updated: 2026-05-29
+permalink: gamevault/meta/tags
+---
+
+# Tag Taxonomy
+
+Keep tags few and meaningful.
+
+- `#moc` — map of content / index notes
+- `#vision`, `#pillars` — north-star docs
+- `#design` — system design docs
+- `#roadmap`, `#milestones`, `#backlog`
+- `#session` — dated work logs
+- `#decision` — decision records (DR-###)
+- `#meta` — protocol / taxonomy
+- Domain: `#dots`, `#netcode`, `#physics`, `#rendering`, `#testing`