sampleplatform CI ("CI - linux" / "CI - windows" checks) is broken across all open PRs — stale baseline + infra failures

[CapThunder19]

Problem

The CI - linux and CI - windows checks (powered by sampleplatform.ccextractor.org) are failing on essentially every open PR right now, regardless of what the PR actually changes.

Evidence

Checked 6 currently-open PRs (#2294, #2298, #2301, #2302, #2304, and one more) — none touching related code to each other and all show CI - linux and/or CI - windows as failing:

PR	CI - linux	CI - windows
#2301 (EIA-608 encoding)	fail "Not all tests completed successfully"	fail same
#2302 (libpng ARM/CMake)	fail same	fail same
#2298 (EIA-608 CC3/CC4)	fail "VM creation failed (ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS). Please contact the administrator."	fail "Not all tests completed successfully"
#2294 (Rust network framing)	fail "Could not complete test, time limit exceeded"	pending
#2304 (DVB subtitle fix, mine)	fail same as #2301/#2302	fail/pending

Three distinct failure modes visible:

1. *Stale comparison baseline: the "compared to test for commit ..." reference used across multiple different PR runs is 2feb09a (dated **2026-04-24), while current master HEAD is ba4a839 (dated **2026-07-26) a *3-month gap. Sample outputs/expected results have likely drifted in that window, producing failures unrelated to any given PR's actual diff (e.g. failures in Broken, CEA-708, General, Options, Teletext, WTV, XDS categories none of which relate to PR Fix silent success return for unhandled DVB string-coded subtitle obj… #2304's DVB-subtitle-only change).
2. Cloud VM provisioning failures: ZONE_RESOURCE_POOL_EXHAUSTED_WITH_DETAILS (PR [FIX] --out report: probe both EIA-608 fields so CC3/CC4 are reported accurately (#2177) #2298) the underlying cloud runner pool appears to be exhausted.
3. Timeouts: "time limit exceeded" (PR fix(rust): harden network block framing #2294).

Suggested fix direction

• Update/automate the baseline comparison commit so it tracks current master instead of a fixed, aging reference.
• Investigate the sampleplatform cloud runner pool exhaustion / timeout issues (may be capacity/quota related).