Minor clarifications for Integration API documentation (integration_port and Traefik config examples)

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While setting up the Integration API following the documentation, I noticed a few small points that might benefit from clarification.

Documentation reference:
https://docs.pangolin.net/self-host/advanced/integration-api

1. integration_port seems required

The documentation shows:

server:
integration_port: 3003 # Specify different port

The comment suggests that this only needs to be set when using a port different from 3003.

However, during setup the Integration API did not appear to start unless integration_port was explicitly defined. It might help to clarify whether:

this field is required, or

it is optional and defaults internally to 3003.

If it is required, the comment could be slightly misleading.

2. Quotes in Traefik rule

The example uses:

rule: "Host(`api.example.com`)"

In YAML this also works without quotes:

rule: Host(`api.example.com`)

It might be worth mentioning whether the quotes are recommended or simply optional.

3. Quotes in service URL

Similarly, the example shows:

servers:
- url: "http://pangolin:3003"

This usually works without quotes as well:

servers:
- url: http://pangolin:3003

Clarifying whether quotes are intentional or just stylistic could help avoid confusion.

4. Minor YAML note (optional suggestion)

A small note reminding users that YAML is indentation-sensitive might help prevent copy/paste errors when applying the config snippets.

Thanks for the great project and documentation 👍