Add system table

Author: lmangani

README.md

@@ -65,6 +65,20 @@ D SELECT * FROM ch_scan("SELECT number * 2 FROM numbers(10)", "https://play.clic
 👉 The [list of supported aliases](https://community-extensions.duckdb.org/extensions/chsql.html#added-functions) is available on the [dedicated extension page](https://community-extensions.duckdb.org/extensions/chsql.html)<br>
 👉 The combined list of [supported functions](https://quackpipe.fly.dev/?user=default#TE9BRCBjaHNxbDsgU0VMRUNUIERJU1RJTkNUIE9OKGZ1bmN0aW9uX25hbWUpIGZ1bmN0aW9uX25hbWUgYXMgbmFtZQpGUk9NIGR1Y2tkYl9mdW5jdGlvbnMoKSBXSEVSRSBuYW1lIElOIChTRUxFQ1QgbmFtZSBGUk9NIGNoX3NjYW4oJyBTRUxFQ1QgbmFtZSBGUk9NIHN5c3RlbS5mdW5jdGlvbnMnLCdodHRwczovL3BsYXkuY2xpY2tob3VzZS5jb20nKSBPUkRFUiBCWSBuYW1lKSBPUkRFUiBCWSBuYW1lOw==) can be obtained using an [SQL Join](https://quackpipe.fly.dev/?user=default#TE9BRCBjaHNxbDsgU0VMRUNUIERJU1RJTkNUIE9OKGZ1bmN0aW9uX25hbWUpIGZ1bmN0aW9uX25hbWUgYXMgbmFtZQpGUk9NIGR1Y2tkYl9mdW5jdGlvbnMoKSBXSEVSRSBuYW1lIElOIChTRUxFQ1QgbmFtZSBGUk9NIGNoX3NjYW4oJyBTRUxFQ1QgbmFtZSBGUk9NIHN5c3RlbS5mdW5jdGlvbnMnLCdodHRwczovL3BsYXkuY2xpY2tob3VzZS5jb20nKSBPUkRFUiBCWSBuYW1lKSBPUkRFUiBCWSBuYW1lOw==)
 
+## System Table
+`chsql` loosely emulates ClickHouse system tables within DuckDB for client compatibility
+
+### Table Views
+- [x] `system.databases`
+- [x] `system.tables`
+- [x] `system.columns`
+- [x] `system.functions`
+- [x] `system.uptime`
+- [x] `system.disks`
+### Scalar
+- [x] `uptime()`
+
+
 <br>