feat: select the TechLog Studio adapter from runtime configuration

Adds TECH_LOG_STUDIO_SOURCE (MOCK | HTTP, default MOCK) to the V2 runtime
config schema so a build can switch createTechLogFeatureInstalledInput
between the mock and HTTP Studio gateways without a rebuild. V1 documents
predate the key and always normalize to MOCK. The HTTP gateway is
constructed with only { operations } per Task 4's actual signature -
no CSRF provider is wired here; that lands with attachCredentials at a
later composition-root task.

Updates every existing Studio test call site to the new required
createTechLogFeatureInstalledInput(context) signature via a shared
tests/helpers/studio-install-context.ts MOCK fixture, so the whole
existing Studio suite keeps exercising the mock adapter unchanged.

tests/runtime-schema/release-manifest.test.ts

@@ -46,6 +46,7 @@ const runtime: Parameters<typeof loadReleaseManifest>[0] = {
       OFFLINE_COMMANDS: "DEFAULT",
     },
     FEATURE_OVERRIDES: {},
+    TECH_LOG_STUDIO_SOURCE: "MOCK",
   },
   configSchema: "V2",
   validationDurationMs: 0,

tests/runtime-schema/runtime-config.test.ts

@@ -165,6 +165,36 @@ describe("runtime configuration boundary", () => {
     expect(result.validationDurationMs).toBe(0);
   });
 
+  it("accepts TECH_LOG_STUDIO_SOURCE and defaults it to MOCK", () => {
+    const defaulted = validateRuntimeConfig(validConfig);
+    expect(defaulted.success).toBe(true);
+    if (defaulted.success) {
+      expect(defaulted.data.TECH_LOG_STUDIO_SOURCE).toBe("MOCK");
+    }
+
+    const explicit = validateRuntimeConfig({
+      ...validConfig,
+      TECH_LOG_STUDIO_SOURCE: "HTTP",
+    });
+    expect(explicit.success).toBe(true);
+    if (explicit.success) {
+      expect(explicit.data.TECH_LOG_STUDIO_SOURCE).toBe("HTTP");
+    }
+
+    expect(
+      validateRuntimeConfig({
+        ...validConfig,
+        TECH_LOG_STUDIO_SOURCE: "LIVE",
+      }).success,
+    ).toBe(false);
+
+    // A V1 document has no such key; normalization must still land on MOCK.
+    expect(validateRuntimeConfig(validV1Config)).toMatchObject({
+      success: true,
+      data: { TECH_LOG_STUDIO_SOURCE: "MOCK" },
+    });
+  });
+
   it("returns only safe boot fields on failure", async () => {
     await expect(
       loadRuntimeConfig({