fix(cli): respect mirror positional arg before --vault flag

Per vrtmrz's review feedback, restore the mirror [vault-path] positional
argument support with correct priority order:
  mirror positional arg > --vault flag > databasePath

Also update --vault help text and CLI README with the new option.

src/apps/cli/README.md

@@ -61,6 +61,9 @@ livesync-cli [database-path] [command] [args...]
 
 - `database-path`: Path to the directory where `.livesync` folder and `settings.json` are (or will be) located.
     - Note: In previous versions, this was referred to as the "vault" path. Now it is clearly distinguished from the actual vault (the directory containing your `.md` files).
+- `--vault <path>` / `-V <path>`: (daemon/mirror only) Path to the vault directory containing `.md` files.
+    - Allows the PouchDB database directory and the actual vault directory to be different locations.
+    - For `mirror` command, the positional `[vault-path]` argument takes precedence over `--vault`.
 
 ### Commands
 
@@ -312,6 +315,7 @@ Options:
   --verbose, -v           Enable verbose logging
   --debug, -d             Enable debug logging (includes verbose)
   --interval <N>, -i <N>  (daemon only) Poll CouchDB every N seconds instead of using the _changes feed
+  --vault <path>, -V <path>  (daemon/mirror) Path to vault directory, decoupled from database-path
   --help, -h              Show this help message
 
 Commands:
@@ -332,7 +336,8 @@ Commands:
   info <path>             Show file metadata including current and past revisions, conflicts, and chunk list
   rm <path>               Mark file as deleted in local database
   resolve <path> <rev>    Resolve conflict by keeping the specified revision
-  mirror [vaultPath]      Mirror database contents to the local file system (vaultPath defaults to database-path)
+  mirror [vaultPath]      Mirror database contents to the local file system
+                           (vaultPath positional arg > --vault flag > database-path)
 ```
 
 Run via npm script:

src/apps/cli/main.ts

@@ -304,11 +304,17 @@ export async function main() {
         : path.join(databasePath, SETTINGS_FILE);
     configureNodeLocalStorage(path.join(databasePath, ".livesync", "runtime", "local-storage.json"));
 
-    // Resolve vault path: --vault flag takes priority, otherwise fall back to databasePath
+    // Resolve vault path: mirror positional argument takes priority,
+    // then --vault flag, otherwise fall back to databasePath.
     // For daemon mode, enable chokidar file watching so the _changes feed picks up events.
     // mirror runs a single full scan and doesn't need continuous watching.
     const watchEnabled = options.command === "daemon";
-    const vaultPath = options.vaultPath ? path.resolve(options.vaultPath) : databasePath!;
+    const vaultPath =
+        options.command === "mirror" && options.commandArgs[0]
+            ? path.resolve(options.commandArgs[0])
+            : options.vaultPath
+                ? path.resolve(options.vaultPath)
+                : databasePath!;
 
     infoLog(`Self-hosted LiveSync CLI`);
     infoLog(`Database Path: ${databasePath}`);