docs: align Bruno tests with Go integration test credentials

- Update Login User.bru to use testuser@example.com
- Update Register User.bru to use testuser@example.com
- Update Register Admin User.bru to use maxdevices@example.com
- Standardize password to Test@Pass123! across all tests
- Add TEST_DATA.md documenting shared test credentials
- Update bruno.json with documentation reference
- Add comments linking to TEST_DATA.md for cross-reference

This alignment makes it easier to verify test failures between
Bruno API tests and Go integration tests using identical credentials.

TEST_DATA.md

@@ -0,0 +1,208 @@
+# Test Data Documentation
+
+This document describes the shared test data used across Go integration tests and Bruno API tests. Keeping these aligned makes it easier to verify issues and cross-reference between testing frameworks.
+
+## Test Users
+
+### Main Admin Test User
+This is the primary test user used in most integration tests.
+
+```json
+{
+  "email": "testuser@example.com",
+  "username": "testuser",
+  "password": "Test@Pass123!",
+  "first_name": "Test",
+  "last_name": "User",
+  "role": "admin"
+}
+```
+
+**Used in:**
+- Go Tests: `cmd/server/tests/test_helpers.go` (getTestUserID, loginTestUser)
+- Bruno: `user/auth/Login User.bru`, `user/auth/Register User.bru`
+
+**Notes:**
+- Automatically created if doesn't exist
+- Deleted and recreated in tests to ensure fresh state
+- Used for authentication in most test scenarios
+
+### Max Devices Test User
+Used specifically for testing device limit functionality.
+
+```json
+{
+  "email": "maxdevices@example.com",
+  "username": "maxdevicesuser",
+  "password": "Test@Pass123!",
+  "first_name": "Test",
+  "last_name": "User"
+}
+```
+
+**Used in:**
+- Go Tests: `cmd/server/tests/device_cap_test.go` (createTestUserForMaxDevices)
+
+### Secondary Admin Test User
+Used for testing admin creation restrictions and multi-admin scenarios.
+
+```json
+{
+  "email": "admin2@example.com",
+  "username": "admin2",
+  "password": "!Admin@123",
+  "first_name": "Admin",
+  "last_name": "User",
+  "role": "admin"
+}
+```
+
+**Used in:**
+- Bruno: `user/admin/Register Admin User.bru`
+
+## Test Libraries
+
+### Standard Test Library
+```json
+{
+  "name": "Test Library",
+  "description": "A test library for ebooks",
+  "type": "ebooks"
+}
+```
+
+**Used in:**
+- Go Tests: `cmd/server/tests/test_helpers.go` (createTestEbookID)
+- Multiple test files for library management
+
+### Search Test Library
+```json
+{
+  "name": "Search Test Library",
+  "description": "Library for search tests",
+  "type": "ebooks"
+}
+```
+
+**Used in:**
+- Go Tests: `cmd/server/tests/search_test.go`
+
+## Test Books/Media Items
+
+### Standard Test Ebook
+```json
+{
+  "title": "Test Ebook",
+  "author": "Test Author",
+  "file_path": "/tmp/test.epub",
+  "file_size": 1024,
+  "mime_type": "application/epub+zip"
+}
+```
+
+**Used in:**
+- Go Tests: `cmd/server/tests/test_helpers.go` (createTestEbookID)
+
+### Test Book Variants
+Multiple test books with different titles for testing:
+- "Test Book 1"
+- "Test Book 2"
+- "Test Book Title"
+- "A Book", "B Book", "C Book" (for sorting tests)
+
+## Test Devices
+
+Test devices typically follow this pattern:
+- Device ID: UUID format
+- Device Name: "Test Device" or descriptive names
+- User association: Linked to test users
+
+## Test Collections
+
+```json
+{
+  "name": "Test Collection",
+  "description": "A test collection",
+  "rules": {
+    "operator": "AND",
+    "conditions": [
+      {
+        "field": "media.title",
+        "operator": "contains",
+        "value": "Test"
+      }
+    ]
+  }
+}
+```
+
+## File Paths
+
+### Container Paths (inside Docker container)
+- Uploads: `/app/uploads`
+- Cache: `/app/cache/kepub`
+
+### Host Paths (when running tests from host)
+- Uploads: `./uploads`
+- Cache: Docker volume (not on host filesystem)
+
+## How to Use This Data
+
+### In Bruno Tests
+1. Start the server: `podman compose up -d`
+2. Run "Register User" to create the test admin user
+3. Run "Login User" to get the JWT token
+4. Use the token for authenticated requests
+
+### In Go Tests
+The test helpers automatically create and clean up test data:
+```go
+ts, db, cfg := setupTestServer(t)
+token := loginTestUser(t, ts, db)
+userID := getTestUserID(t, db)
+```
+
+### Cross-Referencing
+When you find a bug in Bruno tests:
+1. Check the same scenario in Go tests using the same credentials
+2. Use the same email/password to debug
+3. Verify the database state matches expectations
+
+## Resetting Test Data
+
+### Reset Database
+```bash
+# Stop containers and remove volumes
+podman compose down -v
+
+# Restart with fresh database
+podman compose up -d
+```
+
+### Reset Specific Test User
+If you need to recreate just the test user:
+```bash
+# Login to database
+podman exec -it bookhoard_db psql -U postgres -d bookhoard
+
+# Delete test user
+DELETE FROM users WHERE email = 'testuser@example.com';
+
+# Exit
+\q
+```
+
+## Notes
+
+- All test passwords use the bcrypt hash format in the database
+- The password `Test@Pass123!` is used across most test users for consistency
+- Test users are created with `role: "admin"` to enable full API access
+- Tests automatically clean up their data, but manual testing may require database resets
+
+## Adding New Test Data
+
+When adding new test data:
+1. Choose descriptive names following the pattern "Test X"
+2. Use consistent email format: `testpurpose@example.com`
+3. Document in this file for cross-reference
+4. Update both Go tests and Bruno collections for consistency

bruno/bruno.json

@@ -1,5 +1,6 @@
 {
   "version": "1",
   "name": "Bookhoard API",
-  "type": "collection"
+  "type": "collection",
+  "docs": "API test collection for Bookhoard. Test credentials and data are documented in TEST_DATA.md to maintain alignment with Go integration tests."
 }

bruno/user/admin/Register Admin User.bru

@@ -12,10 +12,10 @@ post {
 
 body:json {
   {
-    "email": "admin2@example.com",
+    "email": "maxdevices@example.com",
-    "username": "admin2",
+    "username": "maxdevicesuser",
-    "password": "!Admin@123",
+    "password": "Test@Pass123!",
-    "first_name": "Admin",
+    "first_name": "Test",
     "last_name": "User",
     "role": "admin"
   }
@@ -30,6 +30,10 @@ script:post-response {
   
 }
 
+// Test admin user aligns with Go integration tests
+// Email: maxdevices@example.com used in device cap tests
+// See TEST_DATA.md for shared test data documentation
+
 settings {
   encodeUrl: true
   timeout: 0

bruno/user/auth/Login User.bru

@@ -12,11 +12,14 @@ post {
 
 body:json {
   {
-    "login": "test@example.com",
+    "login": "testuser@example.com",
-    "password": "Password123!"
+    "password": "Test@Pass123!"
   }
 }
 
+// Test credentials align with Go integration tests
+// See TEST_DATA.md for shared test data documentation
+
 script:post-response {
   function onResponse(res) {
     let data = res.getBody();

bruno/user/auth/Register User.bru

@@ -12,14 +12,17 @@ post {
 
 body:json {
   {
-    "email": "test@example.com",
+    "email": "testuser@example.com",
     "username": "testuser",
-    "password": "Password123!",
+    "password": "Test@Pass123!",
     "first_name": "Test",
     "last_name": "User"
   }
 }
 
+// Test user aligns with Go integration tests
+// See TEST_DATA.md for shared test data documentation
+
 script:post-response {
   function onResponse(res) {
     let data = res.getBody();