feat: add flag to disable template insights (#20940)

Closes #20399 

To summarize the original commit messages:

- Do not log stats to the database.
- Return errors on the insight endpoints.
- Update the frontend to show those errors.
- Also fixes an issue with getting the user status count via codersdk,
since I added a test to ensure it was not disabled by this flag and it
was sending the wrong payload.

cli/testdata/coder_server_--help.golden

@@ -277,6 +277,16 @@ INTROSPECTION / PROMETHEUS OPTIONS:
       --prometheus-enable bool, $CODER_PROMETHEUS_ENABLE
           Serve prometheus metrics on the address defined by prometheus address.
 
+INTROSPECTION / TEMPLATE INSIGHTS OPTIONS: 
+      --template-insights-enable bool, $CODER_TEMPLATE_INSIGHTS_ENABLE (default: true)
+          Enable the collection and display of template insights along with the
+          associated API endpoints. This will also enable aggregating these
+          insights into daily active users, application usage, and transmission
+          rates for overall deployment stats. When disabled, these values will
+          be zero, which will also affect what the bottom deployment overview
+          bar displays. Disabling will also prevent Prometheus collection of
+          these values.
+
 INTROSPECTION / TRACING OPTIONS: 
       --trace-logs bool, $CODER_TRACE_LOGS
           Enables capturing of logs as events in traces. This is useful for

cli/testdata/server-config.yaml.golden

@@ -191,6 +191,15 @@ autobuildPollInterval: 1m0s
 # (default: 1m0s, type: duration)
 jobHangDetectorInterval: 1m0s
 introspection:
+  templateInsights:
+    # Enable the collection and display of template insights along with the associated
+    # API endpoints. This will also enable aggregating these insights into daily
+    # active users, application usage, and transmission rates for overall deployment
+    # stats. When disabled, these values will be zero, which will also affect what the
+    # bottom deployment overview bar displays. Disabling will also prevent Prometheus
+    # collection of these values.
+    # (default: true, type: bool)
+    enable: true
   prometheus:
     # Serve prometheus metrics on the address defined by prometheus address.
     # (default: <unset>, type: bool)