refactor: move setNamespace/setTenant/setSharedTables out of abstract Adapter

These were declared abstract on the base, forcing every implementation
to provide them even when the underlying backend has no multi-tenant
or namespace concept. No caller types against the abstract Adapter
to invoke them — every consumer goes through the Usage facade.

- Drop the three abstract method declarations from Adapter.
- Both ClickHouse and Database adapters keep their concrete impls
  (the methods are still needed for current usage).
- Facade now forwards via method_exists, so a future minimal adapter
  (no multi-tenancy, no namespacing) can extend Adapter without
  implementing dead stubs.

Author: lohanidamodar

src/Usage/Adapter.php

@@ -158,28 +158,4 @@ abstract public function sumDaily(array $queries = [], string $attribute = 'valu
      * @return array<string, int> Metric name => sum value
      */
     abstract public function sumDailyBatch(array $metrics, array $queries = []): array;
-
-    /**
-     * Set the namespace prefix for table names.
-     *
-     * @param string $namespace
-     * @return self
-     */
-    abstract public function setNamespace(string $namespace): self;
-
-    /**
-     * Set the tenant ID for multi-tenant support.
-     *
-     * @param string|null $tenant
-     * @return self
-     */
-    abstract public function setTenant(?string $tenant): self;
-
-    /**
-     * Enable or disable shared tables mode (multi-tenant with tenant column).
-     *
-     * @param bool $sharedTables
-     * @return self
-     */
-    abstract public function setSharedTables(bool $sharedTables): self;
 }

src/Usage/Usage.php

@@ -276,7 +276,9 @@ public function sumDailyBatch(array $metrics, array $queries = []): array
     public function setNamespace(string $namespace): self
     {
         $this->flush();
-        $this->adapter->setNamespace($namespace);
+        if (method_exists($this->adapter, 'setNamespace')) {
+            $this->adapter->setNamespace($namespace);
+        }
         return $this;
     }
 
@@ -293,7 +295,9 @@ public function setNamespace(string $namespace): self
     public function setTenant(?string $tenant): self
     {
         $this->flush();
-        $this->adapter->setTenant($tenant);
+        if (method_exists($this->adapter, 'setTenant')) {
+            $this->adapter->setTenant($tenant);
+        }
         return $this;
     }
 
@@ -310,7 +314,9 @@ public function setTenant(?string $tenant): self
     public function setSharedTables(bool $sharedTables): self
     {
         $this->flush();
-        $this->adapter->setSharedTables($sharedTables);
+        if (method_exists($this->adapter, 'setSharedTables')) {
+            $this->adapter->setSharedTables($sharedTables);
+        }
         return $this;
     }