Return `connected` pill to evaluate activity refactor

We need to bring back the `connected` pill on the workspace page to evaluate the consistency of activity reporting.


Previously, it always showed `connected` as opening a workspace in the dashboard was recorded as user activity. When returned, it should only report user activity as outlined in the [internal RFC](https://www.notion.so/coderhq/Definitions-of-Workspace-Usage-Autostop-Dormancy-e7fa8ff782a948c19bbe4ef8315c26cb):

Actions qualifying as usage:
- Starting, stopping, or restarting a workspace,
- Accessing a `coder_app` running inside a workspace through the Web UI (e.g. `code-server` or Web Terminal),
- Connecting to a workspace via `coder ssh`
- Connecting to an application inside the workspace via `coder port-forward`, or via shared port.

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We will associate the pill with the workspace activity refactor experiment (currently enables the feature, should revert the feature before 2.15 release).