(core) change ActiveDoc load and Sandbox call log messages to be aggregation-friendly

Summary:
Takes some numbers embedded in strings and moves them to the context, so
they can be aggregated and trends inspected more easily.

Test Plan: tested manually by looking at logs

Reviewers: dsagal

Reviewed By: dsagal

Subscribers: dsagal

Differential Revision: https://phab.getgrist.com/D4175

app/server/lib/ActiveDoc.ts

@@ -2380,7 +2380,11 @@ export class ActiveDoc extends EventEmitter {
       // took longer, scale it up proportionately.
       const closeTimeout = Math.max(loadMs, 1000) * Deps.ACTIVEDOC_TIMEOUT;
       this._inactivityTimer.setDelay(closeTimeout);
-      this._log.debug(docSession, `loaded in ${loadMs} ms, InactivityTimer set to ${closeTimeout} ms`);
+      log.rawDebug('ActiveDoc load timing', {
+        ...this.getLogMeta(docSession),
+        loadMs,
+        closeTimeout,
+      });
       const docUsage = getDocSessionUsage(docSession);
       if (!docUsage) {
         // This looks be the first time this installation of Grist is touching

app/server/lib/NSandbox.ts

@@ -312,7 +312,11 @@ export class NSandbox implements ISandbox {
       throw new sandboxUtil.SandboxError(e.message);
     } finally {
       if (this._logTimes) {
-        log.rawDebug(`Sandbox pyCall[${funcName}] took ${Date.now() - startTime} ms`, this._logMeta);
+        log.rawDebug('NSandbox pyCall', {
+          ...this._logMeta,
+          funcName,
+          loadMs: Date.now() - startTime,
+        });
       }
     }
   }