feat: remove birth_date field from Member resource

Users who need birthday data can use custom fields instead.
Closes #161

docs/database-schema-readme.md

@@ -115,7 +115,6 @@ Member (1) → (N) Properties
 ### Member Constraints
 - First name and last name required (min 1 char)
 - Email unique, validated format (5-254 chars)
-- Birth date cannot be in future
 - Join date cannot be in future
 - Exit date must be after join date
 - Phone: `+?[0-9\- ]{6,20}`
@@ -169,7 +168,7 @@ Member (1) → (N) Properties
 ### Weighted Fields
 - **Weight A (highest):** first_name, last_name
 - **Weight B:** email, notes
-- **Weight C:** birth_date, phone_number, city, street, house_number, postal_code
+- **Weight C:** phone_number, city, street, house_number, postal_code
 - **Weight D (lowest):** join_date, exit_date
 
 ### Usage Example
@@ -381,7 +380,7 @@ Install "DBML Language" extension to view/edit DBML files with:
 - tokens (jti, purpose, extra_data)
 
 **Personal Data (GDPR):**
-- All member fields (name, email, birth_date, address)
+- All member fields (name, email, address)
 - User email
 - Token subject
 

docs/database_schema.dbml

@@ -122,7 +122,6 @@ Table members {
   first_name text [not null, note: 'Member first name (min length: 1)']
   last_name text [not null, note: 'Member last name (min length: 1)']
   email text [not null, unique, note: 'Member email address (5-254 chars, validated)']
-  birth_date date [null, note: 'Date of birth (cannot be in future)']
   paid boolean [null, note: 'Payment status flag']
   phone_number text [null, note: 'Contact phone number (format: +?[0-9\- ]{6,20})']
   join_date date [null, note: 'Date when member joined club (cannot be in future)']
@@ -153,7 +152,7 @@ Table members {
     **Club Member Master Data**
     
     Core entity for membership management containing:
-    - Personal information (name, birth date, email)
+    - Personal information (name, email)
     - Contact details (phone, address)
     - Membership status (join/exit dates, payment status)
     - Additional notes
@@ -183,7 +182,6 @@ Table members {
     **Validation Rules:**
     - first_name, last_name: min 1 character
     - email: 5-254 characters, valid email format
-    - birth_date: cannot be in future
     - join_date: cannot be in future
     - exit_date: must be after join_date (if both present)
     - phone_number: matches pattern ^\+?[0-9\- ]{6,20}$

docs/feature-roadmap.md

@@ -100,10 +100,10 @@
 **Closed Issues:**
 - [#194](https://git.local-it.org/local-it/mitgliederverwaltung/issues/194) - Custom Fields: Harden implementation (S)
 - [#197](https://git.local-it.org/local-it/mitgliederverwaltung/issues/197) - Custom Fields: Add option to show custom fields in member overview (M)
+- [#161](https://git.local-it.org/local-it/mitgliederverwaltung/issues/161) - Remove birthday field from default configuration (S) - Closed 2025-12-02
 
 **Open Issues:**
 - [#157](https://git.local-it.org/local-it/mitgliederverwaltung/issues/157) - Concept how custom fields are handled (M, High priority) [0/4 tasks]
-- [#161](https://git.local-it.org/local-it/mitgliederverwaltung/issues/161) - Don't show birthday field for default configurations (S, Low priority)
 - [#153](https://git.local-it.org/local-it/mitgliederverwaltung/issues/153) - Sorting functionalities for custom fields (M, Low priority)
 
 **Missing Features:**