feat: add 6 new templates (KeyDB, VictoriaMetrics, Gel, Matomo, Flarum, Leantime)

[ZeroWing-Automator]

Adds a new template for KeyDB — a high-performance, multithreaded fork of Redis by Snapchat.

• Official eqalpha/keydb Docker image
• Auto-generated password via ${password:16}
• Persistent volume for data
• Port 6379 (standard Redis-compatible)
  Closes Get Your Custom Dokploy Templates Built! #152 (partial)

[ZeroWing-Automator]

Adding the remaining community-requested templates to this PR to bundle them up. Note: Skipped Airbyte as they recently deprecated Docker Compose in favor of abctl.

Here are the configuration details for all the new additions:

VictoriaMetrics

• Official victoriametrics/victoria-metrics Docker image (v1.108.1)
• Configurable retention period (default 90 days)
• Persistent storage volume
• Port 8428 (standard VM HTTP API)

Gel (EdgeDB)

• Official geldata/gel Docker image (v6)
• Auto-generated password via ${password:24}
• Persistent volume for data
• Port 5656 (standard Gel/EdgeDB port)

Matomo

• Official matomo:5-apache Docker image
• MariaDB 11 database with auto-generated credentials
• Persistent volumes for app data and database
• Port 80 (Apache)

Flarum

• crazymax/flarum community image
• MariaDB 11 database with auto-generated credentials
• Persistent volumes for forum data and database
• Auto-configured FLARUM_BASE_URL from Dokploy domain

Leantime

• Official leantime/leantime Docker image (1M+ pulls)
• MariaDB 11 database with UTF-8 charset
• Persistent volumes for user files and database
• Port 80

Closes #152 (partial)