Personal Sessions: add create, list, get, revoke, regenerate Admin APIs (#5141)

Introduces some admin API endpoints for Personal Sessions.

- add: Creates a personal session along with its first personal access token, returning both. This is currently the only way to get a personal access token.
- get: Shows the information about a personal session
- list: Shows many personal sessions
- revoke: Revokes a personal session, so it can't be used anymore
- regenerate: Revoke the active personal access token for a session and issue a new one to replace it.

Cargo.lock

@@ -613,6 +613,7 @@ dependencies = [
  "axum-core",
  "bytes",
  "cookie",
+ "form_urlencoded",
  "futures-util",
  "headers",
  "http",
@@ -622,6 +623,8 @@ dependencies = [
  "pin-project-lite",
  "rustversion",
  "serde_core",
+ "serde_html_form",
+ "serde_path_to_error",
  "tower-layer",
  "tower-service",
  "tracing",