refactor: remove 'obsidian' from plugin ID and update branding

- Change plugin ID from 'obsidian-mcp-server' to 'mcp-server'
- Remove 'Obsidian' from plugin description per guidelines
- Update documentation to use new plugin folder name
- Update installation paths to .obsidian/plugins/mcp-server/
- Update package name to match new plugin ID
- Simplify README title and description

manifest.json

@@ -1,9 +1,9 @@
 {
-	"id": "obsidian-mcp-server",
+	"id": "mcp-server",
 	"name": "MCP Server",
 	"version": "1.0.0",
 	"minAppVersion": "0.15.0",
-	"description": "Exposes Obsidian vault operations via Model Context Protocol (MCP) over HTTP.",
+	"description": "Exposes vault operations via Model Context Protocol (MCP) over HTTP.",
 	"author": "William Ballou",
 	"isDesktopOnly": true,
 	"fundingUrl": {