Initial: desk + ncantu placeholder + per-project cursor configs

**Motivations:**
- Centraliser les fichiers Cursor (rules, skills, agents, commands, hooks) par user et par projet

**Root causes:**
- N/A

**Correctifs:**
- N/A

**Evolutions:**
- desk: rules, skills-cursor, agents, commands, hooks, argv/hooks/mcp.json
- ncantu: README placeholder
- 4NK_node, algo, builazoo, ia_local, lecoffre_ng, lecoffre_ng_pprod, lecoffre_ng_test: .cursor contents

**Pages affectées:**
- cursor/desk/, cursor/ncantu/, cursor/<project>/

desk/hooks.json

@@ -0,0 +1,15 @@
+{
+  "version": 1,
+  "hooks": {
+    "sessionStart": [{ "command": "./hooks/session-start.sh" }],
+    "sessionEnd": [{ "command": "./hooks/session-end.sh" }],
+    "subagentStart": [{ "command": "./hooks/subagent-start.sh" }],
+    "subagentStop": [{ "command": "./hooks/subagent-stop.sh" }],
+    "beforeShellExecution": [{ "command": "./hooks/before-shell-execution.sh" }],
+    "afterShellExecution": [{ "command": "./hooks/after-shell-execution.sh" }],
+    "beforeReadFile": [{ "command": "./hooks/before-read-file.sh" }],
+    "afterFileEdit": [{ "command": "./hooks/after-file-edit.sh" }],
+    "stop": [{ "command": "./hooks/stop.sh" }],
+    "postToolUseFailure": [{ "command": "./hooks/post-tool-use-failure.sh" }]
+  }
+}