fix(docs): fall back to direct URL when page verification is rate-lim…

[RajPorus19]

Summary

Fix :GodotDocs (and related commands) failing completely when docs.godotengine.org rate-limits or is unreachable — even though the RST documentation source on GitHub is perfectly reachable.

Details

Problem

M.open() in lua/godotdev/docs.lua calls fetch.resolve_doc_url() which always fetches HTML from docs.godotengine.org to verify the page exists before attempting the RST source fetch. When that host returns HTTP 429 (rate limit):

1. The direct page HTML fetch fails
2. fetch_index() is called as fallback — but it also hits docs.godotengine.org
3. Both fail → callback(nil, nil) → M.open() shows "Could not find Godot docs" and aborts

The RST source fetch (fetch_markdown() → raw.githubusercontent.com/godotengine/godot-docs) is never reached, even though it's on a completely different domain and works fine.

Fix

In M.open() (lua/godotdev/docs.lua): when resolve_doc_url() returns nil (rate-limited / network error), instead of showing an error and aborting, bypass the HTML verification entirely and proceed directly to the RST source:

1. Construct the page URL from common.build_base_url() + common.class_slug()
2. For browser renderer → open the URL directly
3. For buffer/float → call open_from_rst() which fetches RST from GitHub via fetch_markdown()
4. If RST also fails → the existing fallback_renderer logic handles the fallback to browser

This mirrors the proven approach used in real-world setups where docs.godotengine.org aggressively rate-limits shared IPs but

✅ Checklist

• [x ] Tested in Godot version: 4.6.3
• [x ] Tested in Neovim version: v0.12.3
• [ x] Tested on OS / Terminal app: 24.04.1-Ubuntu / gnome-terminal
• [x ] Code follows plugin style guidelines
• [x ] Documentation updated (if needed)

📷 Screenshots (if applicable)

🧩 Related Issues

#40 40 Bug: :GodotDocs fails completely when docs.godotengine.org rate-limits (HTTP 429)

[RajPorus19]

There was an error, i'm turning this into draft until I fix it.