test: add success e2e tests for stream processing commands MONGOSH-2127

[malexandert]

Going to open this up early since I'm running into flakiness on Evergreen and I'm not entirely sure how to resolve it. The error I see coming up most frequently is something like

 [2025/06/03 15:15:41.723] FAILURE:  ()
 [2025/06/03 15:15:41.723] [Timed out 10000ms] expected prompt
 [2025/06/03 15:15:41.723]       + expected - actual
 [2025/06/03 15:15:41.723]       -Current Mongosh Log ID:	683f4860c22a17067f8d8250
 [2025/06/03 15:15:41.723]       -Connecting to:		mongodb://<credentials>@atlas-stream-67ec5d03a32c2e2a2d533eaa-5ml8o.virginia-usa.a.query.mongodb-dev.net/?directConnection=true&tls=true&appName=<REDACTED:notary_signing_key_name>+2.4.0
 [2025/06/03 15:15:41.723]       -Using MongoDB:		Atlas Stream Processing
 [2025/06/03 15:15:41.723]       -Using Mongosh:		2.4.0
 [2025/06/03 15:15:41.723]       -
 [2025/06/03 15:15:41.723]       -For <REDACTED:notary_signing_key_name> info see: https://www.mongodb.com/docs/mongodb-shell/
 [2025/06/03 15:15:41.723]       -
 [2025/06/03 15:15:41.723]       -AtlasStreamProcessing> Atlas Stream Processor: spi683f4861393f8cbf8e529491
 [2025/06/03 15:15:41.723]       -AtlasStreamProcessing> [prompt search starts here]
 [2025/06/03 15:15:41.723]       +/^([^<>]*> ?)+$/m
 [2025/06/03 15:15:41.723]       
 [2025/06/03 15:15:41.723] AssertionError [ERR_ASSERTION]: expected prompt
 [2025/06/03 15:15:41.723]     at new AssertionError (node:internal/assert/assertion_error:454:5)
 [2025/06/03 15:15:41.723]     at /data/mci/b09c072f17e8644b70e629d572a0c179/src/packages/e2e-tests/test/test-shell.ts:238:17
 [2025/06/03 15:15:41.723]     at eventually (/data/mci/b09c072f17e8644b70e629d572a0c179/src/testing/eventually.ts:18:13)
 [2025/06/03 15:15:41.723]     at async TestShell.waitForPrompt (test/test-shell.ts:214:5)
 [2025/06/03 15:15:41.723]     at async TestShell.executeLine (test/test-shell.ts:300:5)
 [2025/06/03 15:15:41.723]     at async Context.<anonymous> (test/e2e-streams.spec.ts:136:27)

which, when referring to this call, implies that the command either didn't run at all or it took too long to return a response? I'm not able to repro the failure when running the test locally, so I'm wondering if you have any ideas on how to proceed

[malexandert]

welp, tests are just failing now because dev is having issues. I'll restart the tasks later once that's sorted

[malexandert]

Ok from a bit more testing, it seems like bumping the timeout for waitForPrompt specifically does smooth out some of the flakes. Gonna see if I can try and minimize the bumped timeouts and then update this PR

[addaleax]

Ok from a bit more testing, it seems like bumping the timeout for waitForPrompt specifically does smooth out some of the flakes. Gonna see if I can try and minimize the bumped timeouts and then update this PR

Yeah, this seems like it would be fine to apply this locally here – is it expected that sp.start() takes a long amount of time, or is it supposed to return fairly quickly?

[addaleax]

Would it make sense to instead wait using eventually() for the assertion below on the first countDocuments()'s return value to be true? That should help with avoiding flakiness from this bit