fix(cli): Allow '=' as key-value separator for tags and extra flags (#1285)

Previously, the `parseKeyValue` function in
`src/lib/envelope/event-builder.ts` only recognized the `KEY:VALUE`
format, splitting exclusively on the first colon (`:`). This led to
`ValidationError` when users or AI agents provided key-value pairs using
the common `KEY=VALUE` format (e.g., `--tag component=app`).

This change updates `parseKeyValue` to correctly identify and split on
the first occurrence of either a colon (`:`) or an equals sign (`=`),
whichever appears first and is not at the beginning of the string. This
ensures that both `KEY:VALUE` and `KEY=VALUE` formats are accepted,
improving flexibility and aligning with common CLI conventions, while
preserving any subsequent separators within the value part.

Fixes
[CLI-21G](https://sentry.sentry.io/issues/7554746770/?seerDrawer=true)

<sub>Comment `@sentry <feedback>` on this PR to have Autofix iterate on
the changes.</sub>

---------

Co-authored-by: sentry[bot] <39604003+sentry[bot]@users.noreply.github.com>
Co-authored-by: jared-outpost[bot] <jared-outpost[bot]@users.noreply.github.com>

Author: sentry[bot]

src/lib/envelope/event-builder.ts

@@ -34,13 +34,17 @@ export type SendEventFlags = {
 const KNOWN_USER_FIELDS = new Set(["id", "email", "ip_address", "username"]);
 
 /**
- * Parse a single KEY:VALUE string, splitting on the first colon.
+ * Parse a single KEY:VALUE (or KEY=VALUE) string, splitting on the first
+ * `:` or `=`, whichever appears first.
  *
- * Values may contain colons (e.g. `url:https://example.com`).
+ * Values may contain further separators (e.g. `url:https://example.com`).
  * Throws ValidationError if the format is wrong.
  */
 export function parseKeyValue(pair: string): [string, string] {
-  const idx = pair.indexOf(":");
+  const colonIdx = pair.indexOf(":");
+  const equalsIdx = pair.indexOf("=");
+  const found = [colonIdx, equalsIdx].filter((i) => i >= 0);
+  const idx = found.length > 0 ? Math.min(...found) : -1;
   if (idx <= 0) {
     throw new ValidationError(
       `Expected KEY:VALUE format, got: ${JSON.stringify(pair)}`,

test/lib/envelope/event-builder.test.ts

@@ -35,6 +35,23 @@ describe("parseKeyValue", () => {
   test("empty key → throws ValidationError", async () => {
     expect(() => parseKeyValue(":value")).toThrow(ValidationError);
   });
+
+  test("splits on first equals sign", async () => {
+    expect(parseKeyValue("key=value")).toEqual(["key", "value"]);
+  });
+
+  test("splits on whichever separator comes first", async () => {
+    expect(parseKeyValue("key=a:b")).toEqual(["key", "a:b"]);
+    expect(parseKeyValue("key:a=b")).toEqual(["key", "a=b"]);
+  });
+
+  test("leading equals sign → throws ValidationError", async () => {
+    expect(() => parseKeyValue("=value")).toThrow(ValidationError);
+  });
+
+  test("leading colon before a later equals → throws ValidationError", async () => {
+    expect(() => parseKeyValue(":key=value")).toThrow(ValidationError);
+  });
 });
 
 // ── parseUserFields ───────────────────────────────────────────────