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>/

4NK_node/rules/4nkrules.mdc

@@ -0,0 +1,156 @@
+---
+alwaysApply: true
+# cursor.mcd — règles d’or 4NK
+language: fr
+policies:
+  respond_in_french: true
+  no_examples_in_codebase: true
+  ask_before_push_or_tag: true
+
+directories:
+  ensure:
+    - archive/
+    - docs/
+    - tests/
+    - .gitea/
+  docs:
+    required_files:
+      - API.md
+      - ARCHITECTURE.md
+      - COMMUNITY_GUIDE.md
+      - CONFIGURATION.md
+      - GITEA_SETUP.md
+      - INDEX.md
+      - INSTALLATION.md
+      - MIGRATION.md
+      - OPEN_SOURCE_CHECKLIST.md
+      - QUICK_REFERENCE.md
+      - RELEASE_PLAN.md
+      - ROADMAP.md
+      - SECURITY_AUDIT.md
+      - TESTING.md
+      - USAGE.md
+  tests:
+    required_files:
+      - cleanup.sh
+      - README.md
+    required_dirs:
+      - connectivity
+      - external
+      - integration
+      - logs
+      - performance
+      - reports
+      - unit
+  gitea:
+    required_files:
+      - PULL_REQUEST_TEMPLATE.md
+    required_dirs:
+      - ISSUE_TEMPLATE
+      - workflows
+    ISSUE_TEMPLATE:
+      required_files:
+        - bug_report.md
+        - feature_request.md
+    workflows:
+      required_files:
+        - ci.yml
+
+files:
+  required_root_files:
+    - CHANGELOG.md
+    - CODE_OF_CONDUCT.md
+    - CONTRIBUTING.md
+    - docker-compose.yml
+    - LICENSE
+    - README.md
+
+documentation:
+  update_on:
+    - feature_added
+    - feature_modified
+    - feature_removed
+    - feature_discovered
+  replace_sections_named: ["RESUME"]
+  rex_required_on_multiple_hypotheses: true
+  archive_obsolete_docs: true
+
+compilation:
+  compile_often: true
+  compile_when_needed: true
+  fail_on_errors: true
+
+problem_solving:
+  auto_run_steps:
+    - minimal_repro
+    - inspect_logs
+    - bisect_changes
+    - form_hypotheses
+    - targeted_tests
+    - implement_fix
+    - non_regression
+
+office_docs:
+  docx_reader: docx2txt
+  fallback:
+    - pandoc_convert
+    - request_alternate_source
+
+dependencies:
+  auto_add_missing: true
+  always_check_latest_stable: true
+  document_changes_in_docs: true
+
+csv_models:
+  treat_as_source_of_truth: true
+  multirow_headers_supported: true
+  confirm_in_docs: true
+  require_column_definitions: true
+
+file_processing:
+  study_each_file: true
+  ask_questions_if_needed: true
+  adapt_code_if_needed: true
+  propose_solution_if_unreadable: true
+
+types_and_properties:
+  auto_correct_incoherences: true
+  document_transformations: true
+
+functional_consistency:
+  always_ask_clarifying_questions: true
+
+frontend_architecture:
+  react_code_splitting: true
+  state_management: ["redux", "context_api"]
+  data_service_abstraction: true
+
+execution_discipline:
+  finish_started_work: true
+
+open_source_and_gitea:
+  prepare_every_project: true
+  gitea_remote: "git.4nkweb.com"
+  required_files:
+    - LICENSE
+    - CONTRIBUTING.md
+    - CHANGELOG.md
+    - CODE_OF_CONDUCT.md
+  align_with_4NK_node_on_creation: true
+  keep_alignment_updated: true
+
+tests_and_docs:
+  update_docs_and_tests_with_code: true
+  require_green_tests_before_commit: true
+
+versioning:
+  manage_with_changelog: true
+  confirm_before_push: true
+  confirm_before_tag: true
+  propose_semver_bump: true
+
+pre_commit:
+  run_all_tests: true
+  block_on_errors: true
+
+---