non-appkit Apps guidance

[arsenyinfo]

Summary

Adds platform documentation for Databricks Apps, split into two reference pages:

• references/platform-guide.md — universal platform rules for ALL apps (AppKit included): SP permissions, resource types & injection, OBO vs SP auth, deployment workflow, runtime environment, compute & limits, HTTP proxy & streaming, common errors.
• references/other-frameworks.md — non-AppKit framework setup: port/host config, app.yaml/databricks.yml, dependency management, networking/CORS, Streamlit gotchas.

SKILL.md routing table updated to point AppKit agents at platform-guide.md and non-AppKit agents at other-frameworks.md.

Documentation safety checklist

• Examples use least-privilege permissions (no unnecessary ALL PRIVILEGES, admin tokens, or broad scopes)
• Elevated permissions are explicitly called out where required
• Sensitive values are obfuscated (placeholder workspace IDs, URLs, no real tokens)
• No insecure patterns introduced (e.g. disabled TLS verification, hardcoded credentials)

[calreynolds]

Light feedback in Slack -- otherwise awesome!!

[MarioCadenas]

databricks apps deploy works too for this I think no?

[arsenyinfo]

Good call — databricks apps deploy in a DABs project directory does validate + bundle deploy + bundle run in one shot. Updated the deployment section to recommend it as Option A.

[MarioCadenas]

do we actually need this? as long as the resource gets added into the app (basically having it declared as a resource in the databricks.yml) once deploy gets done the resource is added to the app, granting the service principal access to it (but maybe I'm missing something)

[arsenyinfo]

You're right — checked the SDK and CLI code: the permission field on app resources is literally "Permission to grant" (SDK godoc), so the backend auto-grants it to the SP on deploy. Removed the manual set-permissions / put-acl commands and replaced the section with a declarative databricks.yml example + default permissions table.