feat: add note context menu with color and metadata controls

- Added PATCH endpoint for updating note frontmatter with YAML parsing and merging
- Added DELETE endpoint to move notes to .trash directory with timestamped filenames
- Implemented note context menu with actions like duplicate, share, favorite, and delete
- Added color picker to context menu with gradient background visualization
- Extended NoteFrontmatter type with readOnly and color properties
- Added YAML frontmatter parser with support

vault/toto/Nouvelle note 2 copy.md

@@ -0,0 +1,20 @@
+---
+titre: Nouvelle note 2
+auteur: Bruno Charest
+creation_date: 2025-10-24T12:24:03.706Z
+modification_date: 2025-10-24T08:24:04-04:00
+catégorie: ""
+tags:
+  - ""
+aliases:
+  - ""
+status: en-cours
+publish: false
+favoris: false
+template: false
+task: false
+archive: false
+draft: false
+private: false
+readOnly: false
+---

vault/toto/Nouvelle note 2 copy.md.bak

@@ -0,0 +1,19 @@
+---
+titre: "Nouvelle note 2"
+auteur: "Bruno Charest"
+creation_date: "2025-10-24T12:24:03.706Z"
+modification_date: "2025-10-24T08:24:04-04:00"
+catégorie: ""
+tags: [""]
+aliases: [""]
+status: "en-cours"
+publish: false
+favoris: false
+template: false
+task: false
+archive: false
+draft: false
+private: false
+readOnly: false
+---
+