Add initial journal file for PostgreSQL dialect version 7

- Created a new JSON file `_journal.json` to track changes and entries.
- Included metadata such as version, dialect, and a sample entry with breakpoints enabled.

drizzle/meta/_journal.json

@@ -0,0 +1,13 @@
+{
+  "version": "7",
+  "dialect": "postgresql",
+  "entries": [
+    {
+      "idx": 0,
+      "version": "7",
+      "when": 1779726518779,
+      "tag": "0000_adorable_shiver_man",
+      "breakpoints": true
+    }
+  ]
+}