feat(telemetry): Sentry + PostHog quality pass (#546)

Comprehensive telemetry quality improvements across Sentry and PostHog, grounded in an audit of the live data plus current best-practice research.

Sentry: job_id/instance_id tags, operational fingerprinting, PII-safe settings context on bug events, web tag population + extension-noise filtering, an early-crash buffer, http status/method kept on breadcrumbs, and a gated-off-by-default performance-tracing re-enable (tracesSampler that zeroes db/redis/queue-poll root spans + drops the Redis integration) with worker job spans and canonical-host cron monitors.

PostHog: history_change SPA pageviews, instance_id super property for fleet rollups, enriched tool_used (formats, byte sizes, is_batch, execution_hint, real error_kind taxonomy), the previously-dead result_saved/batch_processed/ai_bundle_prompted events fired, search click-through, editor + Automate authoring + auth instrumentation, a before_send PII boundary, and minimal opt-in landing-site pageviews.

tests/unit/api/error-report.test.ts

@@ -6,6 +6,7 @@ import {
   resetThrottleForTests,
   safeFormatTag,
   shouldReport,
+  vetSettings,
 } from "../../../apps/api/src/lib/error-report.js";
 
 describe("safeFormatTag", () => {
@@ -132,3 +133,37 @@ describe("errorSignature", () => {
     expect(errorSignature(null)).toBe("Unknown:-:-");
   });
 });
+
+describe("vetSettings", () => {
+  it("keeps numbers, booleans, and short enum-like string values", () => {
+    expect(vetSettings({ quality: 80, lossless: true, format: "png", fit: "cover" })).toEqual({
+      quality: 80,
+      lossless: true,
+      format: "png",
+      fit: "cover",
+    });
+  });
+  it("drops sensitive keys, free-text/PII-shaped values, objects and arrays", () => {
+    // A password, a filename, and watermark text must never reach Sentry; nested
+    // objects/arrays and long strings can carry user data, so drop them too.
+    expect(
+      vetSettings({
+        password: "hunter2",
+        filename: "IMG_1234.png",
+        watermarkText: "Property of Jane",
+        crop: { x: 1, y: 2 },
+        sizes: [1, 2, 3],
+        width: 1024,
+        format: "webp",
+      }),
+    ).toEqual({ width: 1024, format: "webp" });
+  });
+  it("returns undefined for non-objects and when nothing safe survives", () => {
+    expect(vetSettings(undefined)).toBeUndefined();
+    expect(vetSettings("nope")).toBeUndefined();
+    expect(vetSettings([1, 2])).toBeUndefined();
+    expect(
+      vetSettings({ note: "a long free-text field well beyond the safe length" }),
+    ).toBeUndefined();
+  });
+});