Rebrand from MyCrib to Casera

- Update Go module from mycrib-api to casera-api
- Update all import statements across 69 Go files
- Update admin panel branding (title, sidebar, login form)
- Update email templates (subjects, bodies, signatures)
- Update PDF report generation branding
- Update Docker container names and network
- Update config defaults (database name, email sender, APNS topic)
- Update README and documentation

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

README.md

@@ -1,6 +1,6 @@
-# MyCrib API (Go)
+# Casera API (Go)
 
-Go implementation of the MyCrib property management API, built with Gin, GORM, Gorush, and GoAdmin.
+Go implementation of the Casera property management API, built with Gin, GORM, Gorush, and GoAdmin.
 
 ## Tech Stack
 
@@ -156,10 +156,10 @@ Seed files are located in `seeds/`:
 
 ```bash
 # Seed lookup tables (required)
-cat seeds/001_lookups.sql | dokku postgres:connect mycrib-db
+cat seeds/001_lookups.sql | dokku postgres:connect casera-db
 
 # Seed test data
-cat seeds/002_test_data.sql | dokku postgres:connect mycrib-db
+cat seeds/002_test_data.sql | dokku postgres:connect casera-db
 ```
 
 ### Test Users
@@ -187,4 +187,4 @@ This is a full rewrite that maintains API compatibility. The mobile clients (KMM
 
 ## License
 
-Proprietary - MyCrib
+Proprietary - Casera