fix(spec-044): env_kind prioritize cloud_ide over ci (gemini P1)

Gemini cross-review flagged that Codespaces + Gitpod routinely set
CI=true alongside their own markers (CODESPACES, GITPOD_WORKSPACE_ID).
With the original CI-wins ordering from design §4.2 / research.md R1,
real humans working in ephemeral cloud IDEs were being classified as
`ci`, artificially deflating Cloud IDE retention numbers and skewing
the activation funnel.

Reorder the decision tree so cloud_ide is checked before ci. Ordinary
CI runners (without CODESPACES/GITPOD/etc.) still classify as `ci`.

This intentionally deviates from the locked design doc; comment block
updated to explain why and cite the cross-review finding.

Tests:
- Add cloud-ide-codespaces-beats-ci (CI=true + CODESPACES=true -> cloud_ide)
- Add cloud-ide-gitpod-prebuild-beats-ci (CI=true + GITPOD_WORKSPACE_ID -> cloud_ide)
- Existing ci-beats-container case still passes (no cloud-IDE markers).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: claude

internal/telemetry/env_kind.go

@@ -142,8 +142,16 @@ func hasAnyEnv(env map[string]string, names []string) bool {
 
 // DetectEnvKind is the pure classifier that decides env_kind + env_markers
 // from an injected environment map, filesystem prober, OS name, and TTY
-// checker. Ordering is authoritative: CI wins over cloud-IDE wins over
-// container. See design §4.2 / research.md R1.
+// checker. Ordering is authoritative: cloud_ide wins over CI wins over
+// container.
+//
+// NOTE: This ordering deviates from the original design doc (§4.2 / research.md
+// R1) which put CI first. The change is motivated by gemini P1 cross-review:
+// GitHub Codespaces and Gitpod routinely set CI=true alongside their cloud-IDE
+// markers (CODESPACES, GITPOD_WORKSPACE_ID). Real humans in those ephemeral
+// cloud sessions were being classified as `ci`, artificially deflating the
+// Cloud IDE retention funnel. Prioritising cloud_ide over CI keeps interactive
+// human sessions in the right bucket while still catching ordinary CI runners.
 //
 // Inputs:
 //   - env: map of env-var name → value (caller builds this from os.Environ).
@@ -176,12 +184,14 @@ func DetectEnvKind(env map[string]string, fs FileProber, osName string, tty TTYC
 		markers.IsContainer = true
 	}
 
-	// Decision tree (first match wins).
+	// Decision tree (first match wins). cloud_ide is checked BEFORE ci because
+	// Codespaces / Gitpod set CI=true alongside their own markers — see
+	// function doc comment.
 	switch {
-	case markers.HasCIEnv:
-		return EnvKindCI, markers
 	case markers.HasCloudIDEEnv:
 		return EnvKindCloudIDE, markers
+	case markers.HasCIEnv:
+		return EnvKindCI, markers
 	case markers.IsContainer:
 		return EnvKindContainer, markers
 	}

internal/telemetry/env_kind_test.go

@@ -142,6 +142,29 @@ func TestDetectEnvKind_DecisionTree(t *testing.T) {
 			wantKind:    EnvKindCloudIDE,
 			wantMarkers: EnvMarkers{HasCloudIDEEnv: true},
 		},
+		{
+			// Gemini P1: GitHub Codespaces sets CI=true alongside CODESPACES.
+			// Must resolve to cloud_ide, NOT ci, because it's a real human in
+			// an interactive ephemeral session.
+			name:        "cloud-ide-codespaces-beats-ci",
+			env:         map[string]string{"CI": "true", "CODESPACES": "true"},
+			fs:          newFakeFS(),
+			osName:      "linux",
+			tty:         fakeTTY(false),
+			wantKind:    EnvKindCloudIDE,
+			wantMarkers: EnvMarkers{HasCIEnv: true, HasCloudIDEEnv: true},
+		},
+		{
+			// Gemini P1: Gitpod prebuilds run with CI=true but the workspace ID
+			// is present — still a cloud_ide session, not a CI runner.
+			name:        "cloud-ide-gitpod-prebuild-beats-ci",
+			env:         map[string]string{"CI": "true", "GITPOD_WORKSPACE_ID": "abc"},
+			fs:          newFakeFS(),
+			osName:      "linux",
+			tty:         fakeTTY(false),
+			wantKind:    EnvKindCloudIDE,
+			wantMarkers: EnvMarkers{HasCIEnv: true, HasCloudIDEEnv: true},
+		},
 		{
 			name:        "cloud-ide-gitpod",
 			env:         map[string]string{"GITPOD_WORKSPACE_ID": "abc"},